Question: Should You Buy a Home With Popcorn Ceilings?
"After looking at what seems like hundreds of homes that we can not afford, my husband and I finally found our dream home. The home is within our budget, and it's located in a good school district, which is very important to me. Everything about this home is perfect except for one thing. It has popcorn ceilings. My husband says that popcorn ceilings are no big deal, but what would he know? He smokes like a chimney and shows no signs of stopping. He says a popcorn ceiling with asbestos won't kill him any faster. What do you think? We have twin girls who are not yet three. Should we buy a home with popcorn ceilings?"
Answer: I hate to say this, but when it comes to popcorn ceilings, your husband is partially correct. Whether you call them popcorn ceilings, acoustic ceilings, or textured ceilings, it's all the same type of cottage cheesy ceiling. That bumpy stuff stuck to the ceiling. If you're really unlucky, some popcorn ceilings have embedded those 1970-era sparkles.
This reminds me of my neighbor who could not sell her home. She asked me what she could do to improve her odds of selling. I suggested she remove the popcorn ceiling. This was something that had not occurred to her. After the workers scraped away the mess, it revealed a beautiful plaster ceiling perfectly intact. My neighbor liked it so much that she decided not to sell after all. The project encouraged her to tackle other home improvement projects.
Many homes built in the late 1930s through the 1990s have popcorn ceilings or some type of texture applied to the ceilings.
This was before the government discovered that asbestos was a bad thing. According to the EPA, the use of asbestos in textured ceiling paint was banned in 1977. Inhaled in large quantities, asbestos fibers can cause lung disease, scarring of the lungs and lung cancer. However, not all popcorn ceilings contain asbestos. Moreover, if left undisturbed or contained, asbestos is not dangerous but many people still don't want it present in their home.
You might be wondering why would anybody spray a ceiling to start with? I suspect in part it's because they did not want to finish the ceiling or could not conceal imperfections. Sometimes, a popcorn ceiling covers up a bad drywall and mudding job. That's because mudding (applying joint compound) a ceiling is an art. Not every contractor or homeowner turned weekend warrior is an artist. It was also trendy at the time.
You could leave the popcorn ceiling and contain it by painting it, or you could remove it. It's not that expensive to remove, so I would not refuse to buy a home just because it has popcorn ceilings. You can fix that problem relatively easily.
Don plastic gloves to avoid contact with the sample.
Fill a spray bottle with a teaspoon of soap and 16 ounces of water.
Spray a small area to dampen the ceiling.
Use a sharp razor-blade knife, cut out a sample and seal it in the container.
Mail your sample to the lab and wait about a week for the results.
It might not matter to your husband whether the product is dangerous. However, inhaling almost any type of building material is not exactly healthful.
If you both choose to bypass the test but still remove the popcorn ceiling, it would be wise to hire a professional to do the job.
Some people prefer to do the job themselves. If so, you should take precautions.
To be safe, the pros recommend that you wear a respiratory mask. Do not expose body parts to the texture in the ceiling. Wear a long shirt and pants. Cover your feet, your hands, and your head. Because no matter how careful you are, the stuff will fall on you. That's because you are located below falling material.
If you have pets, relocate them to another room. Pets and home remodeling don't always go hand in hand. Especially cats. They are curious creatures and end up stepping in stuff and tracking it all over the house. You don't want to give your cat a bath. Nooo.
Cover the flooring. If you use a plastic sheeting, you could slip and lose your footing. I recommend those large brown rolls of packing paper. Toss drop cloths and cover those with brown paper. That way, when the mess falls on the paper, you can roll it up to discard it.
You can use a garden hose set to a mist option to dampen the ceiling. Work in small areas at a time.
Use a push pole with a blade to scrape the ceiling. This is easier from the floor than walking up and down a ladder to scrape by hand. Do not stand directly under falling plaster.
After the ceiling dries, fill gouges or holes with joint compound, let it dry, then sand. It may require several coats of joint compound to achieve a smooth finish. If you are unhappy with your abilities to finish the ceiling, at this point, you could always hire a drywall expert to finish the last coat of mud.


4.3.2.2 P8: Low frequency power oscillations.
The international standards EN 50 121, EN 50 163, EN 50 238, EN 50 388, and others, define the framework for the electrical compatibility between the rolling stock and the infrastructure systems on electrified railways. However, since the infrastructure systems for historical reasons are not equal in all countries, each national rail administration must define the detailed application of the standards in that country, and specify additional requirements in fields that are not covered by the standards. The present document defines the details of the electrical railway infrastructure in Norway and Sweden, and specifies the electrical compatibility requirements for the rolling stock. In general, these requirements are in accordance with the relevant standards, but certain technical differences exist, also compared to the systems in the other 16.7 Hz countries Germany, Austria, and Switzerland.
P13 Regenerative braking The vehicle must not cause the line voltage to increase above 17.5 kV (S) or 18.0 kV (N), in regenerative braking.
The vehicle must not cause the voltage locally at other types of vehicles to exceed 17.5 kV to any greater extent than what is seen in the existing system (S only).
The table below outlines the tests that are required for approval. The time needed for the tests depend on a) the number of different operation modes for the vehicle, and b) the free time on the closed track the actual time periods for testing. Most tests must be performed night-time. Experience shows that the categories T1 and T2 require at least two nights each plus transport time, and category T3 1-2 days. In Sweden, category T4+T5 is generally also one day due to the transport. It is expected that category T6 is performed at the suppliers workshop or similar facilities.
It should be noted that these approximate time indications are valid only for a vehicle that is in its final and approvable state, with all software functions and all parameters frozen. Any tests required for the supplier's own purposes (i.e., to make the vehicle approvable, or for fine-tuning of software) come in additional and up front.
The test categories T1, T2, and T4 may be performed in either country. The mixed traffic tests T3 must be performed in the country/countries where the vehicle will operate. Test T5 must be performed in Sweden. The tests T6 may be performed anywhere with 16 2/3 Hz or 16.7 Hz supply. For an approval in Norway, parallel measurements in the substation must be made during test T1.
Three different acceleration-brake operation sequences are defined: LOOP, ABAB, and ARO (please refer to section 3.3.4 and 4.4.4).
All vehicles must perform tests up to their speed limit during test category T2. Locomotives must be loaded by a reasonably heavy train (≈1-2 t per kN max. tractive effort, or ≈50-100 t per MW max. power, whichever is the greater) during all tests T1 and T3, in order to create realistic acceleration times. During tests T2, a somewhat lighter load may be used (some 25% of the values above).
Descriptions and characteristics of key functions, such as the current or power control at low line voltages, voltage limitation at regenerative braking, cos(φ)-control, etc.
The test report, including individual conformity statements for each requirement S1-S9 and P1-P16, and including explanations, references to the detailed test results and printouts, and so on.
The international standards (EN, IEC, UIC, etc.) that deal with electromagnetic and functional compatibility between railway vehicles and infrastructure, are kept on a quite general level and do not cover all aspects of relevance for each individual country and national rail administration. Typically, different signalling systems are used in different countries, meaning that specific national requirements apply in addition to the common standards.
In Norway and Sweden, not only the signalling systems, but also the power supply differs significantly in comparison with other 16.7 Hz countries.
It is the objective of the present document to compile all relevant information and all requirements that apply to rolling stock used in Norway and Sweden, with respect to compatibility with the electrical infrastructure and other vehicles; i.e. the power supply, existing rolling stock, and infrastructure systems such as track signalling circuits, telecommunication lines, etc.
Jernbaneverket and Banverket are committed to harmonize, as far as possible, not only their technical requirements, but also their requirements regarding approval procedures and tests. It must be noted, however, that due to a number of technical differences between the two countries, this objective cannot be fulfilled for all requirements.
The document is first and foremost based on the standards EN 50 121 part 1 to 5, EN 50 163, EN 50 238 and EN 50 388. This however does not imply that other standards are not valid.
The document concentrates on the special national conditions that are valid for Norway or Sweden, and on topics that are not completely covered by international standards.
The tests described in the document are considered being type tests. This means that if tests are performed in one country, and the test procedures and conditions are representative also for the other country, then the tests, the recorded data, and the results may also be used for the performance evaluation and approval in the other country, even if the limits are different (i.e., tests in one country can provide data also for the other country).
Requirements regarding the mechanical interaction between the pantograph and the contact line are presented in other documents. Furthermore, the requirements on train control systems, such as ATC (= Automatic Train Control) or ERTMS, and interference with train radio and digital systems such as PCM, ISDN, etc., are not included in this document.
One full version with all sections 1-4. This version is an appendix to Banverkets document BVS 543:19300.
One version with the sections 1-3 only, and section 4 left unused. This version is an appendix to chapter 5 in Jernbaneverkets document JD 590.
One version with the sections 1, 2, and 4 only, and section 3 left unused. This version is an appendix to chapter 4 in Jernbaneverkets document JD 590.
Section 1 and 2 of this document are for information only. The formal and valid requirements are given in section 3 and 4. In case of any conflicts, section 3 and 4 take precedence over section 1 and 2.
Section 3 of this document is under the responsibility of the signalling departments at Jernbaneverket and Banverket, while the power supply departments are responsible for section 4.
Certain parts of section 3 and 4 are harmonised and to some extent equal, in particular the requirements regarding testing. These sections are marked with a vertical line in the left margin, as shown here. Any changes to these sections should be coordinated between the signalling and the power supply departments.
Most requirements apply equally in the two countries. If a requirement is valid solely in one country, this is highlighted with a (Norway only) or (Sweden only) in the level three header for that requirement. Sometimes (e.g., in tables), the shorter (N only) or (S only) is used.
NORWAY AND SWEDEN: Here the parts of the requirement that are common to the two countries are listed. If there are no common requirements, this heading is not used.
NORWAY: Here the requirements that are specific to Norway are listed.
SWEDEN: Here the requirements that are specific to Sweden are listed. The "Sweden only"-section goes on until the next level two, level three, or level four heading, whichever is first.
If a requirement is quantitative, i.e. there is a numerical limit; the accuracy of the limit is given by the number of digits used for the requirement.
Bin Output from a FFT. For example, a FFT with a 1 s window length produces bins at the frequencies 0 Hz (DC), 1 Hz, 2 Hz, . . .
Crest voltage The highest value within one period of the rectified AC voltage. For an ideal sinusoidal voltage, the crest value equals 2 times the RMS value.
C) to introduce already existing vehicles that have not previously been operating in Norway or Sweden.
For this purpose, the document provides detailed information about the infrastructure in the two countries. Some of this information is found in connection with the various requirements, but most is given in the attached appendices.
First time use of rolling stock or reintroduction of rolling stock that have been considered out of use permanently.
Rolling stock that is going to be introduced on sections of track not included in current acceptance.
Changes, both in hardware and software, in rolling stock usage not in compliance with current acceptance.
Modifications of rolling stock in a way that may affect the compliance with the current acceptance.
This means that the requirements in this document are valid for new electrical traction vehicle and old used vehicles that have not been used in normal operation in Norway or Sweden before. An old vehicle used in Norway is not automatically accepted in Sweden.
The requirements in this document can however be discussed when applied on imported old vehicles, except for the Electrical Safety and requirements regarding signalling circuits and psophometric currents. Requirements regarding signalling circuits are always valid due to safety aspects. Requirements regarding psophometric currents are valid due to effects for third party.
Table 1. Use of the requirements (Sweden only).
All requirements are mandatory. Already accepted, but any rebuilds or modifications should aim for improving compatibility, and must not reduce compatibility.
For already accepted vehicles, which are to be put in operation on new lines for which the acceptance is not valid, relevant requirements are valid in order to maintain traffic and not to disturb the electrical infrastructure. Relevant requirement are decided on a case-to-case basis.
Safety requirements and requirements regarding signalling systems and telecommunications are mandatory.
Non-compatibilities with other requirements might be accepted on a case-to-case basis, but only if it can be demonstrated that the requirements are in fundamental conflict with technical requirements from other countries of operation.
Non-compatibilities with other requirements might be accepted on a case-to-case basis, but only if it can be demonstrated that a rebuild would be in fundamental conflict with technical requirements from other countries of operation, or if it can be demonstrated that the cost of a rebuild is out of proportion.
Non-compatibilities with other requirements might be accepted on a case-to-case basis, but only if it can be demonstrated that the cost of a rebuild is out of proportion.
This chapter gives a short introduction to traction power supply systems and track signalling circuits in Norway and Sweden. More specific data about the infrastructure is given as information in APPENDIX 1: Infrastructure data and related information.
In Norway and Sweden the earth resistivity is high in comparison to most of the rest of Europe. This has direct an effect on traction power supply design to avoid disturbing other electrical systems.
In Norway there are 2500 km of electrified railway (2004). The network around the capital Oslo is meshed with both double and single-track lines. Around this centre there are long (> 500 km) single-track lines to other parts of the country. The Norwegian single-phase network is much weaker than in rest of Europe. In some areas the overhead contact line impedance is so large that changes in the power demand from one train may cause voltage variations up to some kilovolts. Both tap changer vehicles, phase controlled vehicles and inverter vehicles with and without filters operate in the network.
The power supply system is of the type 15 kV, 16.7 Hz. It is synchronized with the 50 Hz national grid, i.e. a decentralized system. There is however a small centralized system in the Oslo area consisting of a 55 kV, 16 2/3 Hz single-phase high voltage transmission line fed by one small hydro power station. This system is connected to the contact lines system via 5 substations (which can be located together with rotary converters).
Apart from the small centralized system the power is fed into the traction power supply system by rotary and static (power electronic) converter stations, which convert the energy from 50 Hz, three-phase, to 16 2/3 Hz, single-phase. The number of active converter units in each converter station is adapted to the hourly variation in load demand to allow maintenance and reduce the losses. There is one small hydro power station feeding directly to the overhead contact line system. In normal operation there is often a one-to-one relation between one converter station capacity and load demand form one train. Due to this, low frequency oscillations have often caused severe problems when new vehicles have been introduced.
In normal operation the system is interconnected between the feeding points, but in order to maintain both rail tracks and contact line, sectioning of the system is a common operation mode.
At present, the booster transformer (BT) system, with or without return conductors, is the main feeding system for contact lines in Norway. However, Jernbaneverket plans to build autotransformer (AT) systems for main long distances lines. There are also some series capacitances and one shunt capacitor in the single-phase network in order to reduce inductive contact line impedance, strengthening the voltage and feeding reactive power. The return path for the traction current, regardless of system and apart from return conductors or any extra earth conductors, always comprise both rails, with exception of stations where single rail track signalling circuits occurs.
On electrified lines AC track signalling circuits are used, either double rail or jointless. Most common are 95 and 105 Hz uncoded track signalling circuits. ATC equipment type EBICAB 700 is used on most lines.
In Sweden there are 9 543 km of electrified railway (2004). The railway network is meshed except for the northern part of Sweden. Most of the lines are single track lines except for lines close to Stockholm and the lines between the cities Stockholm, Gothenburg and Malmö.
The power supply system is of the type 15 kV, 16.7 Hz. The system is decentralized and synchronized with the 50 Hz national grid. The power is fed into the traction power supply system by converter stations, which convert the energy from 50 Hz, three-phase, to 16 2/3 Hz, single-phase. The converters are of both rotary and static (power electronic) type. The number of active converter units in each converter station is adapted to the load.
In order to reduce the number of converter stations, the contact overhead line system is also fed by a 132 kV system (a two-phase 2 x 66 kV system with directly earthed midpoint) with transformer substations. This system is used from the middle to the northern parts of Sweden. There is no power generation connected directly to the 132 kV system. The system is fed from transformers connected to the 15 kV 16,7 Hz busbars at the converter stations.
The two feeding systems for contact lines in Sweden are; BT-system (booster-transformer system) with one or two return conductors and AT-system (auto-transformer system). Sometimes also a strengthening wire (reinforcement wire, booster wire) occurs. This is more common in the northern part of Sweden, and this type of reinforcement wire is always used on AT-systems. Its objective is to lower the impedance. Sometimes an additional earth wire is used. This type of earth wire is planned to become standard on AT-system lines. A combined AT/BT-system is currently under investigation for introduction (a first small installation is made).
Most of the railway lines are fed from both ends (double sided feeding). Due to the high earth resistivity booster transformer systems with return conductors are mainly used, when not autotransformer systems are implemented, due to EMC requirements. This causes normally higher line impedance than in the central and south of Europe, where the return current can use the rails and earth all the way to the feeding point. The system is relatively weak with rather high voltage drops. Only DC track signalling circuits exist on electrified lines in Sweden. At some non-electrified low traffic lines, radio block systems are used.
Only one of the rails, the S-rail, is used for the return path of the traction current. This is regardless of what type of feeding system that is being used (BT- or AT-system). The other rail is always isolated, I-rail, and is used for the DC track signalling circuits.
ATC equipment type EBICAB 700 is used on most lines.
05-01-2007: First version, based on the NIM NES-R10 report with the same title as this document, from 27.11.2006.
If the vehicle is designed such that it is possible to climb up on the roof of the vehicle without difficulty and without additional means, Banverket will define restrictions for parking the vehicle under live overhead contact line.
Any valid regulation from the National Electrical Safety Board (Elsäkerhetsverket) for operations of electrical installations must be followed. Information can be found at http://www.elsakerhetsverket.se/ If there is any accessible electrical equipment on the roof of the vehicle, it shall be possible to connect the grounding and short-circuiting tools used by Banverket to earth points on the electrical equipment. Otherwise the vehicle must have own grounding tools. According to Elsäkerhetsverket, grounding via a transformer is not allowed. EN 50 110-1 Operation of electrical installations is applicable to work activity on Swedish railway electrical installations with some exceptions and applications to overhead contact line.
Necessary information about disconnection and grounding of rolling stock either as labels on vehicles or as readily understandable manuals in each vehicle is required in order to handle deviation situations. This requirement does not apply to information which is obvious or can be assumed to be common knowledge for those who do the specific tasks.
Verification shall be made by conformity statements that the rolling stock fulfils standards and regulations.
The conformity statements shall be presented in a report.
In this chapter all requirements regarding compatibility between vehicles and the power supply are compiled. All requirements, when applicable, are valid for one vehicle and for the maximum configuration of vehicles (i.e. multiple units) for which the approval must be valid. This document describes requirements and infrastructure as is. The infrastructure managers are continuously trying to improve the infrastructure in Norway and Sweden. New or newly imported old rolling stock must not however require changes in the existing infrastructure and rolling stock in order to operate properly.
The values in this section refer foremost to stationary or quasi-stationary conditions. For dynamic effects see also section 4.3.8 P8: Low frequency power oscillations and 4.3.9 P9: Electrical resonance stability.
Under normal operating conditions (in accordance with the definition in clause 3.16 in EN 50 163:2004), the traction power supply complies with the requirements for minimum and maximum voltage given in clause 4.1 in EN 50 163:2004, and for Umean useful(zone) and Umean useful(train) for conventional TSI lines and classical lines given in clause 8 of EN 50 388:2005. Exceptions and specifications are given below.
The nominal voltage is 15.0 kV RMS. The voltage at the feeder station busbar is usually adjusted to 16.5 kV RMS independent of load (below max load), or to 16.5 kV RMS with a gently declining characteristic as a function of inductive current in order to improve load-sharing of reactive power between converter stations. Declining characteristic means that the voltage is controlled in such a way that the voltage will drop linearly as a function of the inductive load, and such that the voltage will decrease about 2-5% from 16.5 kV RMS at full and purely inductive load.
There are no requirements for the unspecified period in time in clause 4.1 in EN 50 163:2004 for maximum voltage, if the increased contact line voltage is caused by regenerative braking of rolling stock. This implies that a train may continuously generate up to Umax2 during regenerative braking.
The instantaneous values for the line voltage can be very high. Due to the high harmonic content, a crest factor above 1.8 can occur giving crest values of up to about 32 kV. Please also refer to section 4.3.3 P3: Line voltage distortion.
The line voltage level may change abruptly, due to cut-in or cut-out of substations or feeding points. The jumps may be from any value to any other value within the line voltage interval 10.0 kV to 18.0 kV RMS.
Existing older rolling stock may not have an efficient current limitation as a function of pantograph voltage and can therefore force the line voltage to be low at sections where the distances between traction power supply feeding points are long. Hence it must be expected minimum train voltages of Umin2 = 10.0 kV RMS and Umin1 = 11.0 kV RMS in accordance with definitions in clause 4.1 in EN 50 163:2004.
Existing Swedish vehicles have not been designed to Umax2 = 18.0 kV RMS, and cannot be expected to withstand voltages higher than 17.5 kV RMS.
Rolling stock must be able to operate under voltage conditions given above.
Rolling stock is not allowed to cause voltages outside the limits in EN 50 163:2004. See also section 4.3.7 P7: Current or power control at low line voltage and 4.3.13 P13: Regenerative braking.
Rolling stock is not allowed to cause voltages below the limits in EN 50 163:2004. New rolling stock must not cause the line voltage locally at any existing vehicle to increase above 17.5 kV to any greater extent (amplitude and time duration limited to approximately 5 seconds) than what is already seen in the existing system. A compatibility study according to EN 50 388 must be made, showing that this requirement is met. A train may continuously generate up to 17.5 kV RMS during regenerative braking.
See also section 4.3.7 P7: Current or power control at low line voltage and 4.3.13 P13: Regenerative braking.
Rolling stock ability to withstand the voltage levels must be tested in accordance with EN 50 215:1999, clause 9.15.
Practical short circuit tests on a line as described in EN 50 215:1999, clause 9.15.4 shall not be performed. These tests are to be performed as factory tests instead. See also chapter 4.3.13 P13: Regenerative braking, and its reference to EN 50 388:2005, clause 12, regarding regeneration to a neutral section or a short circuit.
For more details about tests see chapter 4.4. The line voltage must be continuously recorded throughout all test runs, and the correct operation of the train must be documented.
Voltage jump tests must be performed according to chapter 4.4.4.8.
Conformity statement and test report.
Synchronous frequency is within the variation given by EN 50 163:2004, clause 4.2.
Normally the frequency variation is ± 0.033 Hz and under special conditions the variation is ± 0.166 Hz due to frequency variations in three-phase network.
Rolling stock shall be able to operate under frequency variations in accordance with EN 50 163:2004, clause 4.2.
Figure 7: below shows examples of measured line voltage waveshapes.
The line voltage THD may exceed 0.3 p.u. or 30%. Table 4 below gives a typical example of the statistical distribution of the voltage distortion parameters.
Table 4. Line voltage distortion parameters.
The values of this table are based on approximately 20 hours of recordings made during tests with a locomotive on the Borlänge-Ludvika/Krylbo-Frövi-Eskilstuna line sections in Central Sweden, October 2005. Recordings and analysis by L. Buhrkall.
The values at the 99.95% percentile may be taken as worst-case, excluding short transients etc. Please notice that the highest levels of the low-order harmonics (3rd, 5th, and 7th) do not necessarily occur simultaneously.
Higher-order harmonic voltages exist, typically generated by vehicles without any interference filter.
The harmonics specified above may have all possible angles. Typically, the phase angle of the 3rd harmonic is the opposite of that of the fundamental, such that the crest value of the line voltage becomes the highest possible. To a lesser extend, this is also the case with the 5th harmonic.
Rolling stock must be able to function satisfactory when the contact line voltage includes harmonic distortion as described above.
Limit values for generated and conducted current harmonics are specified in section 0 P10: Current harmonics.
Conformity statement and tests. Tests are specified in chapter 4.4.
The conformity statement and the results of the tests and documented function shall be presented in a technical report.
Infrastructure is not equipped with automatic information about neutral sections. Information about the state of the neutral sections is given to driver by optical signals along the line. Manual on board operation is hence permitted.
The normal length is 90 m, but length down to 40 m and up to 350 m exists. In Norway neutral sections of 402 m length is planned for the future to avoid bridging by train with two current collectors.
System separation sections do not exist.
The normal length is 180 m, but length down to 60 m exists. In railway yards neutral sections with lengths of down to 2 m can occur. The neutral sections are normally not earthed, but at narrow bridges and at construction or big maintenance work this may occur.
Requirements are in accordance with EN 50 388:2005, clause 5. Feedback of regenerative braking power should also be brought to zero when entering a neutral section.
Verification shall be made by means of a technical description on how the vehicle behaves when entering neutral sections. The description can include calculations and functional diagrams.
Verification shall be made by means of a technical description on how the vehicle behaves and how the driver shall behave when entering neutral sections. The description can include calculations and functional diagrams.
The conformity statement and verification shall be presented in a technical report.
and concerns only the fundamental.
which can give very misleading results if harmonics are present, and hence shall not be used.
Figure 8: Allowed power factor for the fundamental. For the area that requires stability investigations see also chapter 4.3.8 and 4.3.9.
Requirements are in accordance with EN 50 388:2005, clause 6.
NOTE 1: At very long feeding distances, the application of a capacitive cos( can lead to network breakdown, over voltages, exceedance of power transfer stability limits, or other dynamic effects, within the normal operation range of line voltage and active power. At lower voltages, however, it could be beneficial from a power transfer point of view to let cos() go even lower than 0.95 (cap), but in case this possibility is utilized, it must be treated in accordance with clause 10 in EN 50 388:2005 (section 4.3.8 and 4.3.9 in this document). I.e., a stability study must be performed in order to document that the vehicle is stable at these conditions. Please also refer to the section 4.3.7 P7: Current or power control at low voltage.
NOTE 2: Even if the power factor is allowed to decrease freely (inductively) during regeneration (electrical braking), according to EN 50 388:2005, clause 6, in order to keep the voltage within limits, it is required that the power factor is not inductive (below 0.95) when the voltage goes below 16.5 kV. Please also refer to section 4.3.13 P13: Regenerative braking.
As an alternative to the requirements in EN 50 388:2005, it is recommended that the limits defined in figure 8 below are used (also in this figure, the power factor refers to the fundamental, as in EN 50 388:2005).
The figure is valid for all possible situations (all instantaneous RMS-values, but transients excluded) with the restrictions mentioned above.
Using the figure means that the applicant does not have to perform the calculations given in EN 50 388:2005, clause 6.2. The verification can be made by measurements, see section 4.4.
NOTE: It is acceptable that the requirement for cos(φ) ≥ 0.95 in driving mode is violated when operating at conditions with ice or frost on the overhead contact line. Under these conditions, a higher reactive current may be used at no or low power in order to maintain a continuous current for the traction and auxiliary converters. Approximately 15 A rms inductive reactive current per current collector is allowed.
NOTE: The value 0.95 in the figure above is expected to be improved to 0.98 in the future for inductive power factor, as stated in EN 50 388:2005.
The requirements shall be verified by calculations, using measured power factors at different operating conditions, in accordance with EN 50 388:2005, clause 6, 13 and 14. As an alternative, the verification can be made by tests and the use of figure 8. The conditions for measurements and tests are specified in chapter 4.4.
The conformity statement and verification shall be presented in a technical report. The report shall include the calculations or a description of the calculations when calculations in accordance with EN 50 388:2005 have been made. Also measured values shall be presented in the report. If the alternative method of the requirements and verification is being used the report shall include figures presenting the measured results. A description of the used instrumentation shall be included. If cos(φ) control is used in the vehicle, the corresponding control characteristics shall be documented. If capacitive cos(φ) is applied in traction, line power versus voltage diagrams shall be included for lines with various line lengths / impedances.
Maximum allowable train current is given in EN 50 388:2005 Table 2 with specifications and exceptions as given below.
Due to the mixture of line having different power supply capacity, the Norwegian lines are divided into classes of maximum allowable train current (Imax). These classes and where they apply is given in register of infrastructure (Network Statement).
NOTE: There are additional limitations of the maximum line current in regenerative braking, see section 4.3.13 P13: Regenerative braking.
For older rolling stock without automatic current limitation, maximum allowable train current (Imax) must however be considered in each individual case.
Norwegian infrastructure is not prepared for automatic current selection. An on board installed technical current or power selector which limit the current or power demand of the train to the given electrical capacity of the line is not required. In case such a selector is not installed, the maximum current limiting must be carried out manually by the driver.
Note that if voltage dependent current limitation is not used, voltages below the line voltage level requirements given in EN 50 163:2004 (see 4.3.1 P1: Line voltage levels) may occur when collecting Imax on some sections, even when no other trains are present in the section.
The value for Sweden in Table 2 in EN 50 388:2005, clause 7, is valid for vehicle drawing current in tractive mode. During regenerative braking the current can exceed this value, due to cos(φ)-control (if present) in order to keep the voltage within limits.
Requirements are in accordance with EN 50 388:2005, clause 7.
NORWAY AND SWEDEN: No specific documentation needed.
Due to long feeding distances and consequently large voltage drops, it is necessary to adapt the level of power consumption depending on the line voltage.
NOTE: Application of such a voltage dependent current or power limiting device may increase the risk for low frequency oscillations. See section 4.3.8 P8: Low frequency power oscillations.
NOTE: Application of a capacitive cos() at low line voltages may increase the power that can be transferred at long feeding distances, but may also lead to instabilities due to line voltage collapse or feedback effects. See section 4.3.5 P5: Power factor and 4.3.8 P8: Low frequency power oscillations.
NOTE: The requirements in EN 50 388:2005, clause 7, are based on line current. Control based on power can be easier to realize and fulfils the basic requirements (avoid breakdown of voltage and let the vehicle find a stable working point) as well. Hence it is allowed for the applicant or manufacturer to design this control as a power limitation control, even though it is not strictly according to the standard. If the limitation is designed as a power control, the current shall not exceed the limits given in EN 50 388:2005, clause 7.2. It must however be stated how the limitation is designed.
Verification shall be made by a technical description of how the requirements are fulfilled. Verification shall also be performed by tests on a weak single fed line by measuring the voltage and current. The tests are specified in chapter 4.4.
The conformity statement and verification shall be presented in a technical report. The tests shall at least be presented in a U-I-diagram with the limits drawn in the diagram for both traction and braking. As additional information, a U-P-diagram should be given.
NOTE: The whole subject of low frequency power oscillations is currently under investigation, and the requirements in section 4.3.8 reflect present (mid-2009) knowledge. A thorough update of the section is expected within the next two years.
Figure 9: Example of an unstable vehicle, low frequency power oscillations.
See also Appendix A4.1.1 for the background of low frequency oscillations.
Both Norway and Sweden have a large number of rotary frequency converters feeding the railway network with 16 2/3 Hz from the public 50 Hz grid. These converters are synchronous-to-synchronous machines and have no damping windings on the motor side. Hence the pole angle oscillations – which have an eigen-frequency of about 1.6 … 1.9 Hz – are poorly damped. This characteristic is very specific for both countries and leads to special requirements which may not exist in other networks. However, it is possible to meet these requirements as various projects have shown.
If an oscillation is excited, the rotor in the synchronous-to-synchronous converter oscillates relative to the synchronous frequency (rotates faster and slower than the synchronous speed in a cycle with the oscillation frequency), and the single phase voltage and frequency may vary from the stationary value (frequency oscillations up to and possibly above 3% of fn can be used as indicative values). This means that the zero crossings of the voltage may not be as predictable as indicated by the specified stationary frequency variation. Experience has showed that vehicles may have problems to work properly or at all when this type of oscillations occurs.
Periodic changes in active power in the single-phase network occurring at the eigen-frequency of the converter can be greatly amplified, typically 10 times, through the converter unit. This means that periodic changes in the active power at the single-phase side can cause 10 times higher power oscillations on three-phase side of converter. This may cause noticeable voltage fluctuations and power oscillations in public utility grid. The eigen-frequency of the converters depends on the size of the converter unit, the number of units running in parallel, the characteristics of the utility network feeding the station, etc.
Figure 9 shows an example of an unstable vehicle (an example from Norway including measurements in the substation).
The figure shows measured voltage and current together with calculated active and reactive power in a situation when a vehicle makes the power system unstable.
All values are referred to their respective quasi-stationary values. It is important to notice that the vehicle active power, reactive power and hence current oscillates more or less 180 degrees phase shifted relative the line voltage amplitude oscillation. This has a de-stabilizing impact on the system and should be avoided. Oscillations are also expected to cause mechanical stress and degeneration of the converter units.
More information on dynamic behaviour of rotary converters is given in Appendix A5.
It is important to notice that the installed power of a train may in some cases reach or even exceed the rated power of a rotary or static converter. Low traffic density implies that the voltage controller in a vehicle and in the converter unit can work directly against each other in a one to one relation. Hence low frequency oscillations of about 3-4 Hz have also been observed together with static converters in some cases.
Long feeding distances and the correspondingly high line impedance can also lead to low frequency oscillations if the vehicle controllers are inadequately structured and parameterised.
By generating or consuming reactive power (cos(φ)-control), the line voltage at the location of the vehicle can be lowered or raised in a controlled manner, hence reducing the voltage drop along the line. However, this control strategy has the potential of creating low frequency oscillations in the feedback loop line voltage → reactive power → line voltage. The line impedance as well as the number of vehicles in a feeding section acts as gain factors in this loop.
A simple time domain simulation model of the oscillatory rotary converter has been developed. The aim is to provide an impression of how the rotary converter behaves. This model can be used by railway vehicle manufacturers for compatibility studies prior to the first test with new vehicles. However, experience has shown that the model due to its simplicity gives more optimistic results regarding stability than real life measurements. Description of the model can be found in Appendix A5.4.
It is possible that the rail network in future will be divided into different classes based on low frequency oscillations and each class with different requirement.
Figure 10: Load step response of an isolated rotating converter (load step to zero).
The vehicles shall not cause low frequency oscillations, neither by feedback effects (including cos(φ)-control) nor by repetitive controller action. Furthermore, the vehicles must not obstruct damping of low frequency oscillations that have been excited by other vehicles or events in the network. Any already excited oscillation, e.g., due to a sudden load change, shall be well damped. This means that the damping of the ≈ 1.6 Hz oscillation that is seen in the load step response of an isolated rotating converter (see figure 10) must not be reduced when a vehicle is present on the line, compared to the damping (time constant ≈ 3 s) of the converter itself.
These requirements must be assured for all relevant operational conditions, including maximum number of vehicles in a feeding section, and outage of a substation and single-side feeding. The precise conditions and consequently the parameters depend on the application of the vehicle (e.g. freight locomotives or rapid mass transit).
A train must have a stable behaviour close to a converter station with an installed power equal to or lower than the rated power of the train. The same train shall be stable at 60 km distance from the same substation on a line with single-side feeding.
The vehicle must be immune against the oscillations in such a way that its operation is not improperly influenced by oscillations caused by the vehicle itself, or by other vehicles or events in the network.
Repetitive controller action (e.g. in the adhesion control or line current limitation) must not take place with deterministic intervention frequencies between 1.0 and 2.0 Hz.
Feedback loop effects must not cause oscillations within the frequency range of 1.0 to 5.0 Hz. Such effects should in general also be avoided for other frequency ranges.
For new vehicles, a stability study according to EN 50 388:2005, clause 10 shall be performed in its relevant parts. It is recommended that the simulation results (step 10 of the compatibility process) are presented before the tests in the real railway system begin.
See Appendix A4.1.2 and A4.1.3 of this document for further information on stability studies.
How often and for which reasons oscillation occurs: Experience shows that some oscillation in phase position for rotary converters may be difficult to avoid, e.g. when wheel slip and slide protection or protective relays are activated. When no extraordinary causes exist, such as the ones described above, the rolling stock is expected not to cause oscillations.
Any oscillation that is initiated by the vehicle, by other vehicles, or by any event in the power supply, will normally be damped by the converters as shown in appendix A5. Vehicles must not react to an oscillation in a way that maintains the oscillation or obstruct the damping of the oscillation.
The relationship between oscillations in 3-phase power and single-phase power at converter units: A large amplification indicates that the converter is exposed to power variations that excite oscillations in an unfavourable way.
Oscillation amplitude for contact line voltage and/or power: Increased amplitude deteriorates the conditions for both existing and future rolling stock. A definite limit will be such that new or modified vehicles shall not cause worse maximum values than values existing today.
Numerical requirements for the vehicle-infrastructure interface are under investigation. Until this investigation has been finished, the requirements are as described above, and the verification has to include measurements in the converter station.
The verification shall be done by testing for typical operational as well as one or several worst case situations. These situations shall be as similar as possible to those investigated in the simulation study. A test plan according to EN 50 388:2005, clause 10, step 12, is required before starting the tests. The tests are specified in chapter 4.4 Validation and tests.
At present, additional measurements in the converter station are required to ensure proper low frequency behaviour. Details are given in chapter 4.4 Validation and tests.
The documentation consists of the conformity statement, the simulation report, and the test report. The simulation report shall point out the stability limit in terms of line impedance, number of vehicles and substation power rating, and show which oscillation frequency would be created if this stability limit is exceeded.
Note that the simulation report must be ready at the time of writing the test plan (see chapter 4.4.4 Requirements prior to testing). The test results shall also be presented in a report. The report shall include diagrams with the relevant variables (voltage, current, active and reactive power, etc.) both full-scale and zoomed during oscillations as in figure 9, i.e., in a way such that it is possible to read how the different variables change relative each other.
See Appendix A4.2.1 for the background of electrical resonance stability.
Both networks have similar and demanding conditions in view of resonance stability, since they include vehicles and static converters with partially large filters, a dedicated 132-kV transmission system (Sweden only, Norway has a small 55-kV system), long feeding distances between substations, and in the future an increasing amount of cables in the 15 kV network. Autotransformer systems also have a lower resonance frequency than other supply systems.
For values regarding line resonances see Appendix 1 section A1.5.9 and A1.510, which gives numerical values for booster transformer and autotransformer systems.
The relevant characteristic for resonance stability is the frequency response (or small signal behaviour) of the input admittance Y(f) seen from the pantograph into the vehicle. If the real part Re(Y(f)) is negative at any frequency f, then the vehicle is capable of causing instabilities when combined with critical resonance points in the power supply system or other vehicles. These instabilities will appear as self-excited oscillations at the corresponding frequency f. In such a case, the vehicle is said to be "active", otherwise it is "passive".
Vehicles must be passive for all frequencies above the frequency fg as defined below. This is the acceptance criterion as required by EN 50 388:2005, clause 10, step 7.
The criteria for electrical resonance stability are applicable for inverter vehicles only. fg is 87 Hz.
For all types of vehicles special attention must be taken if passive filters are used. For frequencies where the filters are capacitive the filters must be well damped and the filters must not produce overvoltages.
The frequency response Y(f) is preferably obtained by measurements, but for the time being, real-time simulations with hardware-in-the-loop are also accepted. The test specification for frequency response measurements used by Swiss State Railways (SBB) and Austrian State Railways (ÖBB) describes a reasonable measurement set-up and scale. The upper frequency limit for evaluation of Y(f) depends on the applied inverter and controller technology and has to be selected at least so high that no active behaviour can be expected beyond it.
Hardware-in-the-loop simulations must include different operation points (typically zero power, maximum traction power, and maximum braking power).
No stability study for the full power supply system has to be performed, provided that the vehicle meets the requirements as defined above for inverter vehicles. For vehicles which do not meet these requirements, a full study according to EN 50 388:2005, clause 10 has to be performed by the vehicle manufacturer or by the infrastructure owner on the applicants costs. For vehicles equipped with passive filter, the applicant must show simulations or calculations which confirm that the filters are well damped at frequencies where the filters are capacitive, and that there is no risk for resonances or overvoltages, according to EN 50 388:2005, clause 10.
Tests are to be performed in connection with other tests. The voltage shall be recorded and analyzed with respect to harmonics, see chapter 4.4 Validation and tests. In particular, this is valid for the mixed traffic tests with test runs in areas with heavy other traffic.
Simulation report, conformity statement, and validation/test report.
Numerical data giving the frequency response Y(f) has to be delivered in a commonly used electronic format (ASCII files, Excel, Matlab), with a maximum resolution of 1/3 Hz from the line frequency up to 1 kHz or up to the sample frequency of the converter control, whatever is the higher frequency. The choice of using the sampling frequency comes from the experience that some vehicles have had problems above the Nyquist frequency.
The circuit diagram and component parameters of the line-side circuits of the vehicle must be included in the report for comparison purposes.
Note that the simulation report must be ready at the time of writing the test plan (see chapter 4.4.4 Requirements prior to testing).
Evaluation of the voltage and the harmonics measured during the tests shall be presented.
These requirements are not a part of EN 50 388: 2005, but due to the high harmonic content in the Norwegian and the Swedish network, which in turn causes high peak value in the line voltage (see section 4.3.3 P3: Line voltage distortion), these requirements are needed in order not to worsen the situation.
The current harmonics generated by the vehicle are not allowed to exceed the levels in the following table. The individual harmonics are related to the rated current of the vehicle.
Table 5. Limits for individual current harmonics.
Even harmonics are implicitly limited by the THDI –value.
Individual inter-harmonics in the current shall not exceed more than 3% of the fundamental rated current. The limits presented above for current harmonics are under investigation and shall be considered as target values. The limits represent the 95%-percentile of the measured line current harmonics.
The vehicle design must consider the high levels of the line voltage harmonics, meaning that the vehicle must have sufficiently high input impedance not to act as an "interference vacuum-cleaner" or amplifier. This applies to both the passive input impedance (determined mainly by the main transformer and line filters, if any), and the active input impedance below 90 Hz in case harmonic anti-control is used, e.g., in order to stabilize the DC link voltage.
The harmonic current limits of table 5 above apply for harmonic voltage distortion levels up to the 90% percentile of table 4 in section 4.3.3 P3: Line voltage distortion.
Verification of the requirement shall be made by test measurements. Tests are specified in chapter 4.4.
The conformity statement and the results of the tests shall be presented in a technical report.
Zone 2 covers the whole line and 20 % or more of adjacent lines with disconnect time usually less than 0.3 s. Zone 2 is triggered by a current step of 200 A or a voltage step of 2 kV during 0.2 s.
Time delayed over current protection covering approx. 50% of the line. Used as primary protection covering the whole line at branches without distance protection (often short, single fed switching yards). Approximate setting: 0.8-1.6 kA, delay time 0.2-3 s (inverse or constant).
High speed over current protection at some branches.
Thermal protection of the overhead contact wire at some high loaded branches/lines.
Automatic circuit breaker re-closing at most branches, if the circuit breaker has tripped due to distance, over current, 100 Hz and under voltage protection. Re-closing is executed 5 s after the breaker has tripped first time, and then 30 s and 180 s, respectively, after the previous re-closing attempt has ended. If the last attempt fails, the breaker is blocked and must manually be closed from the dispatch centre.
In general, the 100 Hz protection in the static converter stations orders disconnection if the current harmonics around 100 Hz exceed given levels.
Under voltage protection disconnecting if the voltage is below approx. 6 kV for more than 20 s.
Combined under voltage and over current protection disconnecting if the voltage is below approx. 10 kV and the current is above 300 A for 0.4 s.
High speed over current protection (< 50 ms for static and < 10 ms for numerical relays): Normal setting for the current is 1.5-2.0 kA.
Two-step distance protections in combination with a current/voltage jump relay. The second step is activated by the current/voltage jump relay, set at 175 - 450 A and 2 kV. The first step covers 65 - 85% of the line, step two covers 100 % of the first line and from 30 % up to 50 % of the next line.
Time over current protection with an approximate setting of: 0.8-1.2 kA, delay time 1-3 s (inverse or constant).
Thermal protection against prolonged overloading of the contact line.
Normally each line has a test resistor of 640 Ω. Before the circuit breaker for a line is closed, a voltage is applied to the line via this test resistor, and if the impedance is sufficiently high the circuit breaker closes.
Automatic circuit breaker re-closing exists on most lines, operating if the circuit breaker has tripped due to distance or over current protection. Re-closing is executed 5 s after the breaker has tripped the first time, and then again 60 s after the previous re-closing attempt has failed and is terminated. If the last attempt fails, the breaker is blocked and must manually be closed from the dispatch centre.
Under voltage protection with a normal setting of 9 kV, 0.5 s.
The disconnection time for a fault with a high current (> 1.5 kA) is less than 150 ms.
Requirements are in accordance with EN 50 388:2005, clause 11.
Note that in case the breaker capacity is higher than the highest short circuit current in the power supply system, the breaker shall open immediately for all faults in the vehicle. When applying this rule, it must be considered if the vehicle is also operating in other countries where higher short circuit currents may occur. In that case the breaker shall be staged for faults on the primary side of the transformer.
Technical report and conformity statement.
relay protection systems commonly used in both Norway and Sweden is over current relays with different tripping time (see chapter 4.3.11 P11: Relay protection and coordination). These over current protections disconnect the line if the inrush currents exceed the trip levels and/or trip times.
Maximum magnitude of the inrush current from the transformer or any other equipment in the vehicle shall not exceed 2.0 kA (peak value) during the two first periods, 120 ms, after breaker closure. This value is valid when connecting the vehicle to a stiff 16.5 kV, 16.7 Hz voltage source. The requirements are valid for a complete traction unit which can be more than one vehicle.
When several vehicles are connected (multiple unit operation) to the 15 kV system, it is desired that breaker operations on the vehicles are unsynchronized, i.e. that there are different delays imposed on each vehicle.
Verification shall be made by calculations and tests. The tests are specified in chapter 4.4.
Technical report with conformity statement and test results.
Normally, most of the regenerative power from rolling stock will be consumed by other trains. Temporary sectioning of the network may to a large extent reduce, or completely disable, the single-phase network's ability to absorb regenerative power feedback.
Regenerative power feedback may in some sections be limited even further as mentioned below, due to special reasons. All rotary converters and some static converters can feed power back to the 3-phase network. Some static converter stations cannot receive power feedback from the single-phase network at all. In these stations the energy may be "pushed" forward by shifting the phase angle of the output voltage.
Due to the contact line's thermal capacity, and in order to enable the protection for outgoing lines to detect a short circuit while at the same time rolling stock feeds back regenerative power, the power supply is divided into classes of allowable regenerative current. These classes and where they apply is given in register of infrastructure (Network Statement).
Norwegian infrastructure is not equipped for automatic power selection. An on board installed technical current or power selector which limit the current or power demand of the train to the given electrical capacity of the line is not required. In case such a selector is not installed, the maximum current limiting must be carried out manually by the driver.
Figure 11. Suggested cos(φ)-control in regenerative braking.
Figure 12. Suggested power limitation and cos(φ)-control in regenerative braking.
Requirements for regenerative braking in EN 50 388:2005, clause 12 must be fulfilled. Furthermore, it is not allowed to regenerate power to a neutral section. Feedback of regenerative braking power should be brought to zero when entering such a section.
Vehicles must not continue to feed back power if the requirements for maximum voltage limit given in section 4.3.1 in this document are exceeded, but there is no requirement for the durations of unspecified period described in EN 50 163:2004, table 1, subsection f) given for regenerative power feedback.
A train must not feed back more regenerative power than the limit for the section on which the train is currently operating.
If a system, which automatically stops feeding back power from the train when a short-circuit occurs in the actual section, can be documented to have adequate performance, then the restrictions due to the protection's ability to detect short circuits can be lifted.
New rolling stock must not cause the line voltage locally at any existing vehicle to increase above 17.5 kV to any greater extent (amplitude and time duration limited to approximately 5 seconds) than what is already seen in the existing system. A compatibility study according to EN 50 388 must be made, showing that this requirement is met.
A train may continuously generate up to 17.5 kV during regenerative braking.
NOTE: There are several possible technical solutions in order to meet this requirement. One possible solution is to limit the line voltage at the new rolling stock to 17.5 kV. Another solution is a control of cos(φ) during regeneration (please also refer to section 4.3.5 P5: Power Factor), as suggested by the figures 11 (red crossed area) and 12.
Testing of regenerative braking must be carried out in accordance with EN 50 388:2005, section 13 and 14.
Verification that the vehicle does not regenerate power to a neutral section or to a contact line that is disconnected from the power supply system, or to a short circuit, shall be based on conformity statements and functional descriptions. No practical tests on sites in Norway and Sweden are required.
Verification of the voltage limiting function shall be made by test measurements. The tests are specified in chapter 4.4.
Verification that the vehicle does not cause the line voltage locally at any existing vehicle to increase above 17.5 kV to any greater extent than what is already seen in the existing system, may be by means of calculations presented in a separate report.
Conformity statement. Tests shall be documented in test reports with diagrams presenting the results. Functional descriptions must be presented, showing how the vehicle/s act when entering a neutral section or when a short circuit occurs, both close to the vehicle and at a far distance.
For 1000 V post: 100 - 630 A (large variations, local limits are described in the Network statement). For 400 V post: 63 A.
The 50 Hz facilities are from local distribution grid. Variation in output voltage must be expected to be according to the allowed medium-voltage supply characteristics in EN 50160. The 16.7 Hz facilities are supplied from the overhead contact line via a step-down transformer with ratios from 15:1 kV to 16.5:1 kV and without automatic tap-changing. Variation in output voltage must be expected according to the transformer ratios and the given line voltage variation in 4.3.1 P1: Line voltage levels.
These facilities are supplied from the overhead contact line via a step-down transformer with ratios from 15:1 kV to 16.5:1 kV and without automatic tap-changing. Variation in output voltage must be expected according to the transformer ratios and the given line voltage variation in 4.3.1 P1: Line voltage levels.
The train pre-heating systems must meet all of the following requirements.
For all systems the following apply: Automatic or technical interlocking devises in the train, or manual operating routines are required in order to prevent interconnecting the power supply from stationary pre-heat posts, other potential external power supplies, or supply through the train pantograph.
For 1000 V systems the connection plug must be designed in accordance with UIC 552.
For 400 V systems the contact type must be a circular pin plug 436-6 with pilot contact (L1-L2-L3-N-PE-pilot). Connections in accordance with UIC 554-1, plate IV.
The design of the connection to the pre-heating installation must be in accordance with UIC 550 and UIC 552.
To ensureselectivity, the first peak of the inrush current, when connecting the vehicle to a pre-heating installation, must not exceed 2.0 kA (peak) at 1000V, 16.7 Hz.
Verifications shall be made by technical and functional descriptions.
Verifications shall also be made by tests. The tests are specified in chapter 4.4.
Conformity statement, and a technical report which shall include the test results.
Both Jernbaneverket and Banverket are members of European Railway Energy Settlement System (ERESS). This system allows automatic transfer of data such as time and date, energy demand and GPS-position from the train energy measurement system.
Requirement P15 is expired and replaced be an updated requirement in onother Bane NOR document.
This can refer to heating of driver cabins in some cases, but not whole trains.
If vehicles have equipment that demands 400/230 V, 50 or 16,7 Hz power supply from local main supply or auxiliary systems the installation must be in accordance with UIC 554 in applicable parts. Note that these types of connections are very rare in Sweden and exist foremost on non-electrified lines.
At conditions with ice or frost on the overhead line, arcs between contact wire and pantograph can result in DC components in the traction current. Measurements on existing vehicles have shown that DC currents can flow through the primary of the main transformer of the locomotive or traction unit, with levels exceeding 40 A continuously for up to 60 seconds, and with short-time (a few seconds) levels up to 70 A.
The requirements regarding other topics than electric compatibility captured in this document is to be clarified as a part of the overall compatibility process which is described in JD 590 chapter 1.
Documentation which contains estimations, calculations, or previous measurements of interference currents according to the requirements S1-S6 is required. If such documentation cannot be made available, a preliminary test must be performed on a closed track before any other tests are performed. See also the requirements in section 3.2.1 to 3.2.6.
EMC test regarding radiated emission shall be performed by the manufacturer (or applicant) at the factory before any tests on railway lines in Norway or Sweden. See section Feil! Fant ikke referansekilden., Feil! Fant ikke referansekilden..
Testing of new vehicles on the railway infrastructure is very costly and shall be kept to a minimum for the benefit of all involved parties in long term. In order to reduce the risk of a failure of some tests as well as to document vehicle characteristics which can not be tested directly, simulations shall be performed by the vehicle manufacturer. It is recommended that the simulation results are presented to and discussed with Jernbaneverket and/or Banverket prior to the first tests with the new vehicle.
This concerns low frequency power oscillations (see 4.3.8) and electrical resonance stability (see 4.3.9) and is based on EN 50388:2005, clause 10, steps 1 to 11 of the compatibility study.
Documentation of current limitation as function of voltage is required.
Documentation of the voltage limitation function when using regenerative brake is required.
A test plan shall be presented to Jernbaneverket and/or Banverket before any measurements or tests are carried out. The test plan shall contain a description on how the tests are performed (i.e. what lines shall be used, closed track or mixed traffic and so on) and on the vehicle constellation (load, weight and so on). Furthermore, the test plan shall include a description of the instrumentation and measurement methods that will be used and how the instrumentation is calibrated. This information shall also be included in the test reports.
The tests specified below can to a wide extent be coordinated with the tests regarding signalling systems and telecommunication (S-requirements).
Table 6 below defines the test categories T1-T7, and outlines the minimum number of successful tests specifically addressing the requirements P1-P13.
Table 6. Test categories and general test plan.
T1 Closed track, rotating converters 4 ABAB sequences and 2 ARO-sequences in each end of the line, all in each train configuration.
(Plus additional tests for S-requirements; the data from these tests must be analyzed also for all relevant P-requirements).
T2 Closed track, static converters 4 ABAB sequences and 2 ARO-sequences in each end of the line, all in each train configuration.
6 voltage jump tests. (Plus additional tests for S-requirements; the data from these tests must be analyzed also for all relevant P-requirements).
T3 Mixed traffic 8 hours of effective operation on the specified lines. All data must be analyzed for all relevant P- and S-requirements.
The Tests T1, T2, T4, and T6 can be performed in either country. The tests T3 must be performed in the country/countries where the vehicle is going to operate.
Table 7. Suggested test sites.
T1 Hønefoss-Nesbyen on the Bergen line. Gemla-Lessebo on the Alvesta-Kalmar line.
T2 Lillestrøm-Gardermoen, Gardermoen Airport line. Eskilstuna-Nykvarn on the Eskilstuna-Södertälje line.
T3 Oslo area. Borlänge area (Borlänge-Krylbo, Borlänge-Ludvika).
T6 Any location with posts for train heating supply.
Figure 13: Supply conditions for T1 tests, P-requirements.
Figure 14: Supply conditions for T2 tests, P-requirements.
The test line must be single-end supplied from one rotating converter in island operation. There must be no other trains activated or in operation on the test line. It is recommended that the test permissions allow for operation without ATC.
For an approval in Norway, measurements in the feeding converter station are required in addition to the measurements on vehicle. The activities in the converter station must be carried out according to Jernbaneverkets instructions.
The test line must be single-end supplied from one or two static converters. Since these converters are not designed for island operation, the remaining network must be connected in the supply end. There must be no other trains activated or in operation on the test line. It is recommended that the test permissions allow for operation without ATC.
The mixed traffic tests must be performed by running in timetable-like operation in areas with heavy traffic as well as low traffic, and lines which are fed from rotary as well as static converters. For Sweden, these trips shall also include driving on lines fed by the 132 kV system.
The supply must be the strongest possible. Please refer to the detailed description of these tests in section 4.4.4.9 below.
The tests must be performed at adhesion conditions that are good enough to allow the vehicle to reach full power, but also poor enough to cause frequent wheel-slip. Track-watering equipment must be used if the tests are performed at so good natural adhesion conditions that wheel-slip is not seen, and sand must be used in case the natural adhesion is very low such that full power is not reached.
All tests shall be performed with one vehicle alone, and with the maximum configuration of vehicles (i.e. multiple units) for which the approval must be valid.
Locomotives must be loaded by a reasonably heavy train (≈2 t per kN max. tractive effort, or  100 t per MW max. power, whichever is the greater) during all tests T1 and T3. During tests T2, a somewhat lighter load may be used (some 25% of the values above).
Figure 15. ABAB (Acceleration-Brake-Acceleration-Brake) operation sequence.
Figure 16. ARO (Acceleration-RollOut) operation sequence.
The train must be operated according to the ABAB and ARO speed profiles shown in figure 15 and 16 below, during the tests specifically addressing the P-requirements.
All vehicles must perform tests up to their speed limit during test category T2. During the test categories T1 and T3, the maximum speed is typically given by the speed limit of the line (or, in the case of locomotives, by the load wagons), meaning that the sequences must be terminated at a lower speed.
Tests of voltage jumps shall be performed on a weak double end fed line where one of the feedings shall be switched on and off when the vehicle is fairly close to that station.
The train is accelerated with maximum tractive effort. When the maximum power is reached, the feeding condition is switched. A minimum of 3 successful tests with positive voltage jump (double feeding switched on) and 3 tests with negative voltage jump (double feeding switched off) must be performed.
NOTE: This is not the same test that is specified for DC inrush current for Sweden in chapter 3.2.1 S1: DC track circuits. The tests shall be performed at a location where the short-circuit current is greater than 20 kA, i.e. Ik > 20 kA. In Sweden this means tests directly outside Ockelbo converter station with connection to the 132 kV system, and the maximum number of converters running in Ockelbo, Borlänge, Häggvik and Ånge. In Norway this means tests at Oslo S with all converter unites in the surrounding stations running (Asker, Alnabru, Lillestrøm, Jessheim, Holmlia and Smørbekk).
The tests shall be performed with the maximum configuration of the vehicle (i.e. maximal number of units in multiple operation for which the approval must be valid). At least 10 trials of breaker closures must be performed if the breaker closure is synchronized to a voltage zero crossing. If the breaker closure is not synchronized to the voltage zero crossing, at least 25 trials of breaker closures shall be performed. All trials must be within limits for acceptance.
The current shall be recorded, and the whole course of the inrush current (instantaneous values) for each trial shall be presented after the tests.
These tests refer to the requirement regarding inrush currents in chapter 0,P14: Train pre-heating systems. Verifications shall be made by tests of at least 25 trials of inrush current tests, apart from the description mentioned in clause 0, when the vehicle is connected to a heating post. No specific test site is specified.
The current shall be recorded and the whole course of the inrush current (instantaneous values) for each trial shall be presented after the tests.
The verification of the requirements shall primarily be made by measurements, if not stated otherwise.
Figure 18: Transducer position and recommended measuring equipment.
All measurements shall be performed with adequate voltage and current transducers (transformers and/or active transducers such as Rogowski coils and Hall transducers.
Sampling instruments as shown in figure 18 are recommended. For measurements of high frequency phenomena, such as the Norwegian signalling circuit interference, a sampling frequency of approximately 50 kHz is recommended together with an anti-aliasing filter with a cut of frequency of approximately 20 kHz.
It is required that adequate anti-aliasing filters are used. The cut-off frequency of the anti-alias filter for the current measurement must be higher than the highest frequency of interest, i.e., higher than 17 kHz for Norway (FTGS track circuits) and higher than 6 kHz for Sweden (psophometric currents). The sampling frequency must be well above two times these values. It is recommended that all raw data be streamed directly to a storage device (DAT recorder, hard-disk, or similar) for later post-processing and analysis, in addition to the on-line supervision. For the signal processing see chapter 4.4.5.2 below.
Figure 18 below shows an example of the recommended principle of data recording and analysis, and how to install Hall transducers to measure the DC-current. It is recommended that the speed signal be taken from the vehicle control rather than via GPS, since the test lines comprise numerous tunnels without GPS coverage.
The tolerance of the overall signal chain including transducers, signal conditioners, A/D converters, and data analysis, must be determined before the tests. A measurement error of less than ±1% at the fundamental, and less than ±5% of any of the stated interference requirements, is expected.
Also the tolerance of the phase angle of the voltage and current fundamentals must be determined.
The principles of the data analysis, as well as the tolerances, must be described and presented before the tests, as a part of the test plan for the accepting authority.
Figure 19: Suggested post-processing of the recorded data.
Active power versus RMS line voltage (1.2 s), including the limit curves according to EN 50 388 section 7.2, figure 1.
Reactive versus active power, including the limit curves according to figure 8 in section 4.3.5 P5: Power factor.
Figure 19 below shows the suggested analysis method, based on a sampling frequency of the raw data of 50 kHz.
The comparably short RMS times of 60 ms are required in order not to mask out any low-frequency oscillations.
For FFT analysis, Hanning windows are recommended.
Other types of measurement and evaluation methods, than the recommendations above, can be discussed, but the applicant must then show how these measurements will be carried out and what accuracy will be achieved.
Information about number of repetitions and approximate location for the various tests. Based on this, the applicant must evaluate whether the results can be considered as typical and representative for the later use of the rolling stock, or if special conditions not included in the tests may potentially lead to future problems.
Discussion of the results and evaluation and a conclusion whether each requirement is fulfilled or not, i.e. a confirmative statement for each requirement.
A summary report (or a summary as a part of the whole report) where the test results are summarized with remarks and observations, especially incompatibilities and exceedances of limits.
Furthermore, a general technical description containing a principle block diagram of the traction circuits of the vehicle is required.
4.5.2.18 Maximum active power consumption and feedback [MW] at current collector as function of speed [km/h].
4.5.2.20 Maximum power consumption and regeneration [MW] as function of contact line voltage [kV]. Power consumption for passenger coaches if the vehicle is a locomotive are to be added.
All data that describe curves, such as the tractive effort versus speed, must be given as Excel tables.
Power system simulation software SIMPOW® and the additional module TRACFEED® Simulation are used.


DJ Khaled, his fiancée Nicole Tuck, and his future in-laws need lots of love and support right now. The Khaled/Tuck family received some devastating news late Sunday night, as reports that Nicole's younger brother Jonathan Tuck was murdered over the weekend (Sunday, Feb. 4) hit the internet. At 25 years old, Tuck died at St. Barnabas Hospital after being shot.
The crime against the 25-year-old is still under investigation, as police work diligently to figure out exactly what happened and find the person responsible for the murder. So far, authorities have learned that Tuck was shot in the face in a Bronx apartment.
Tuck was reportedly at the apartment — which was less than a mile from Tuck's residence — to buy weed. Tuck allegedly got into an argument with his murderer while there, leading officers to assume he was shot after the drug deal went bad.
Meanwhile, the second-floor residence stayed barricaded off well after the murder took place, as police look for more evidence to tie Khaled's soon-to-be brother-in-law's murder to the drug deal before ruling everything else out.
"I don't know anything about the show, I just know that I was excited to perform and rip it down … and our performance was trending worldwide," he told The Hollywood Reporter after being asked his thoughts on the show's drop in ratings.
The "I'm the One" artist, who usually keeps his political views to himself, also participated in a skit highlighting parts of Michael Wolff's book Fire and Fury. Khaled alongside Hillary Clinton, Cher, John Legend, Cardi B and Snoop Dogg read sections of Wolff's less-than-flattering (but brutally honest) view of America's 45th president.
"My son loves Rihanna, and he had a talk with Jay-Z. That's what I like doing, bringing my son around all greatness," Khaled shared.
Send the Khaled/Tuck clan some well-wishes in the comments and SHARE this article.


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After Prince Andrew scandal, Princess Beatrice's royal wedding details revealed
Rasha Ali
There's a royal wedding on the horizon this spring.
Princess Beatrice of York and Edoardo Mapelli Mozzi will be getting married on May 29 at the Chapel Royal in St. James's Palace, Buckingham Palace announced Friday.
The Queen will host a private reception for the newlyweds in the gardens at Buckingham Palace.
Princess Beatrice is the elder daughter of Prince Andrew and Sarah Ferguson, the Duke and Duchess of York. The news of her wedding details comes after Andrew, the Queen's second son, announced in November he was stepping away from his royal duties due to controversy over his past friendship with convicted American sex offender Jeffrey Epstein.
Princess Beatrice, 31, got engaged to Mozzi, CEO of architecture/design studio Banda Property, in September while on vacation in Italy. She was previously in a long-term relationship with American-born Dave Clark, whom she broke up with in 2016.
After their engagement announcement, the property tycoon posted photos on his Instagram account with a sweet caption: "You will never be alone my love, my heart is your home. Hand in hand, today, tomorrow and forever."
Mozzi is father to a young son, Wolfie, from a previous relationship with American architect and designer Dara Huang.
Beatrice isn't the first in her family to marry a commoner. Her sister, Princess Eugenie, also got married to her long time boyfriend, Jack Brooksbank, in October 2018. Their wedding was just five months after Prince Harry and Duchess Meghan got married.
Princess Eugenie shared in her sister's exciting news by posting a throwback photo of her and Beatrice as kids.
"She's so excited…. Today the family announced Beatrice will marry Edo on 29th May 2020. Very proud of this moment," she captioned the photo.
Princess Beatrice's nuptials will come on the heels of a hectic few months for the royal family. First, at the tail end of 2019, Andrew made headlines over his connection to Epstein and eventual decision to step back. In early January, Prince Harry and Duchess Meghan made the same decision, though for very different reasons. (In a speech shortly after the headline-making decision, Harry said the couple wanted to continue serving "the queen, the commonwealth and my military associations, but without public funding. Unfortunately, that wasn't possible.")
In a statement announcing the change in his public role, Prince Andrew said he continued to "unequivocally regret my ill-judged association with Jeffrey Epstein."
Federal authorities are continuing their investigation into the disgraced financier despite Epstein's death by suicide in August in a Manhattan detention center where he was awaiting trial on sex trafficking charges.
Shocking headlines – and pictures – popped up in January 2015 when an American woman living in Australia, Virginia Roberts Giuffre, 35, alleged in court documents that she was groomed by Epstein and his associates to sexually service Epstein's powerful friends when she was a young Florida teen.
She said she was compelled to have sex with Andrew three times, in New York, the U.S. Virgin Islands and in London, starting when she was 17.
Andrew emphatically denied knowing anything about Epstein's alleged crimes and to having any sexual contact with Giuffre.
Contributing: Maria Puente, Hannah Yasharoff and Leora Arnowitz

redpajama_set_name: RedPajamaCommonCrawl


Some terrific results again from the weekend – a couple of disappointments too but such is life! Well done to everyone.
Sonia Panek is still on fire with her Under 13 Div 2 side – they haven't lost a game to date! A 19 goal win on Saturday just adds to the season this group of champions are enjoying! Branchy's crew were back on track this week and they beat Queenscliff by 3 – nothing like a tight one to keep everyone on their toes!
They don't get much tighter than the Under 15 Div 2 team which finished 16 all! Better than a loss! Well done Darcy and girls.
April, Kylie and the Under 15 Div 1 side had a ripper game and there was no way this determined group were going to drop this game after going down by two the first time they met Queenscliff. Great determination!
Colleen's Under 17 Div 2 had a tight one too which is always good. Well done ladies on your two-goal victory. The 17 Div 1 team had it a bit easier and enjoyed a tidy victory. With a number of teams not fielding Under 17 teams this season, these girls will have a couple of quiet weeks; however, they won't be able to take the foot off training wise as their next game, after the bye, will be Torquay again. Keep training and hopefully, you will be able to organise some match training in the meantime.
Sue, Cath and the Under 13 Friday night girls had a tight one and unfortunately they went down by 3 goals. Well done to this group of silent achievers – who trip into Geelong every Friday night.
Likewise, our Under 11 teams are really firing and while their results are unofficial – we know that they are going extremely well!
Elise and the Under 19 girls met their match and went down by 7. On the bright side, it was really only the first quarter so there is something to work on.
D Grade (Div 3) didn't have their best day and suffered a disappointing loss. Div 2 and Div 1 both enjoyed comfortable wins and Premier Division bettered their previous 12 goal victory over Queenscliff to a 37 goal one on Saturday. Come the end of the season, that percentage may well be crucial – so keep up the great work!
Still, Barwon Heads is looking very strong across the board – testament to the hard work from our players and coaches!


We are very pleased to announce that we have received 38 team registrations for the 2016 Airborne Delivery Challenge. This is a record for the UAV Challenge! The Airborne Delivery Challenge is open to high-school aged students from around the world. Only the top twenty teams will qualify, and their technical report and video is due on August 18. We can't wait to read all the entries. The teams that have registered are from Australia, USA, China, Puerto Rico, Egypt, India and Pakistan. The event will take place in Calvert, near Ipswich Queensland September 20-21.


The purpose of this podcast is to inform viewers on the importance college student satisfaction has within student affairs departments and higher education institutions.
To illustrate the importance of service learning and civic engagement in higher education.
To demonstrate the need for assessment and accountability of service learning and civic engagement in higher education.


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OVERDOSE ANTIDOTE Thousands of people overdose with Tylenol or other acetaminophen-containing drugs each year, leading to liver damage. Researchers found a way to repair the liver damage in mice.
Experimental anticancer drugs may help protect against liver damage caused by acetaminophen overdoses. In mice poisoned with the common painkiller, the drugs prevented liver cells from entering a sort of pre-death state known as senescence. The drugs also widened the treatment window: Mice need to get the drug doctors currently use to counteract an overdose within four hours or they will die, but the experimental drugs worked even 12 hours later, researchers report August 15 in Science Translational Medicine.
If the liver-rescuing results are verified in clinical trials, this therapy may buy time for people who accidentally or intentionally overdose on Tylenol or other medications containing the painkiller acetaminophen. In the United States, such overdoses occur more than 100,000 times a year and are the leading cause of acute liver failure. Many people get treatment on time or recover on their own, but some require emergency liver transplants. And 150 people on average die of acetaminophen poisoning each year. Currently, doctors treat such overdoses with N-acetylcysteine, an antidote that must be given within eight hours of ingesting a potentially fatal dose. Some people don't make it to a doctor in time, and will die or need transplants.
In the study, untreated mice died within 18 hours. But mice given the new drugs survived at least a week until researchers sacrificed the rodents to examine their livers. The anticancer drugs work by blocking a signal from a tumor growth-stimulating protein called TGF-beta, which is activated by inflammation provoked by the overdose. When unchecked, TGF-beta sends a stress signal that puts liver cells in senescence, liver specialist Thomas Bird of Cancer Research UK Beatson Institute in Glasgow and colleagues report.


As investors, we're always told that "past performance is no indication of future performance". But if investors aren't to consider performance, how should they assess investment managers when choosing a managed fund?
There are many different factors to review, but as a starting point, there are two broad areas to consider.
The first is the business itself – is it profitable? Does it seem stable and likely to have longevity? Some simple research into the asset manager business itself can help provide some clarity and comfort for potential investors.
The second is the investment team and their process. In relation to other functions there also needs to be appropriate resources and skill sets to adequately fulfil the legal, compliance and administrative functions that are needed in operating the fund.
In relation to investment themed items, investors should consider five main categories.
Understandably, the quality of the investment team is key to the success of any managed funds.
Experience – how long has the team been managing money?
Track record – what investment strategy or approach is being implemented today and is it the same as that which existed when the track record was built? Have they shown they are good at it and have the capacity and insights to add value?
Team size and depth – how large is the team? It doesn't necessarily mean that a larger team is better, but do they have the appropriate resources within the team to be able to implement the investment process? Some approaches are more resource intensive than others. Also, does the team have stability? Ideally, you want a good level of continuity and cohesiveness among team members.
The investment process involves identifying and selecting investments, such as stocks, for possible inclusion in the final portfolio.
Assessing an investment process includes trying to understand where a team's investment ideas come from. Is it purely from their own thoughts and ideas, or do other factors come into play? There can be a whole range of these, including broker research and insights, industry conferences, economic related readings, and company and industry related meetings.
Next, look at how the detailed company research is conducted and by whom. That is, are the various members of the investment team specialists, focusing their knowledge and efforts on particular sectors or stocks? Or do they take more of a generalist approach and cover a range of different sectors and stocks?
It's also important to understand the screening process – that is, what screens or rules are applied to the full range of investment options that are available. As an example, this might include 'screening out' companies that are felt to have too much debt on their balance sheet or not a high enough level of interest cover. Or it could involve screening out companies that don't meet governance or social impact requirements, such as tobacco or gambling companies.
Finally, what range of stocks are available for possible inclusion into the portfolio? Is there a defined ranking of these stocks, or perhaps another type of scoring or categorisation process conducted?
The stock research and portfolio construction are related, but are very different roles and require different skill sets.
After all the hard work of the stock research has been done, it's important to then understand how the best stock ideas make their way into the final portfolio… and at what weighting? Ideally, the stocks with the stronger level of conviction will have a higher weighting within the portfolio, but how does this process work?
It's not just about seeking to achieve the best possible return, but also how the assessment of managing risk within the final portfolio is conducted.
For example, it's not a good outcome for a portfolio to perform poorly due to an unknown factor or event that hadn't been identified – let alone assessed.
For a fund manager, this involves identifying and understanding what the potential risks are and what impact they may have on the portfolio should they play out.
The fee level is certainly something that should be assessed, but it's not as simple as saying the lower the fee the better.
Rather, it's about assessing if the fee level associated with a fund is at a reasonable and appropriate level for the type of fund that it is. As an investor, are you getting value for money? For example, a higher fee may be warranted if the investment provides a higher return.
At the end of the day, when net returns are looked at (that is, the return the fund provides after taking fees into account), it can easily be seen if the fund has delivered good value.
Each fund or investment strategy usually has a particular investment style or approach.
Certain styles – and hence funds – tend to have different characteristics of how they typically perform in different market conditions. For instance, a fund could seek to outperform a strong market, or it could focus on minimising losses in a weak market.
When a fund's investment strategy is implemented on a consistent and repeatable basis, it provides a greater level of comfort and predictability as to how a fund may perform under certain market conditions.
This is called being 'true to label', and makes it much easier for investors to identify and select a fund to play a particular role or meet a more defined need within their overall portfolio.
At the end of the day, it's about trying to gain a level of comfort that a fund can and will perform well and meet its stated investment objective.