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Electrical Axis
Electrical Engineering Notes and Articles
Fault Analysis
Circuit Analysis
Electrical Notes and Articles
electric protection power system protection protective relaying
What is the Advantage of IDMT in Protective Relaying?
In protective relaying there are two philosophies available to effectively achieve selectivity and coordination by time grading two philosophies are available, namely:
Definite time lag (DTL), or
Inverse definite minimum time (IDMT).
Traditionally, design engineers have regarded medium- and low-voltage networks to be of lower importance from a protection view, requiring only the so-called simpler type of IDMT overcurrent and earth fault relays on every circuit. In many instances, current transformer ratios were chosen mainly based on load requirements, whilst relay settings were invariably left to the commissioning engineer to determine. Most of the times, the relay settings had been chosen considering the downstream load being protected without an effort to coordinate with the upstream relays.
Read: Basic Guide in Power System Protection
However, experience has shown that there has been a total lack of appreciation of the fundamentals applicable to these devices. Numerous incidents have been reported where breakers have tripped in an uncoordinated manner leading to extensive network disruption causing longer down times or failed to trip causing excessive damage, extended restoration time and in some cases loss of life.
In Definite Time Lag or DTL, the relays are graded using a definite time interval of approximately 0.5 s. The relay R3 at the extremity of the network is set to operate in the fastest possible time, whilst its upstream relay R2 is set 0.5 s higher. Relay operating times increase sequentially at 0.5 s intervals on each section moving back towards the source as shown below,
Definite Time Lag or DTL
The problem with this philosophy is, the closer the fault to the source the higher the fault current, the slower the clearing time – exactly the opposite to what we should be trying to achieve.
Read: IEC 61850 Logical Nodes and Data Classes in Power System Automation Data Modelling
On the other hand, inverse curves as shown in the figure below which describes operating faster at higher fault currents and slower at the lower fault currents, thereby offering us the features that we desire. This explains why the IDMT philosophy has become standard practice throughout many countries over the years
Although not appreciated by many engineers, the widespread use of inverse definite minimum time overcurrent and earth fault (IDMT OCEF) relays as the virtual sole protection on medium- and low-voltage networks requires as much detailed study and applications knowledge as does the more sophisticated protection systems used on higher voltage networks.
Applying IDMT in the System
When deciding to apply IDMT relays to a network, a number of important points have to be considered. Firstly, it must be appreciated that IDMT relays cannot be considered in isolation. They have to be set to coordinate with both upstream and downstream relays.
Their very purpose and being is to form part of an integrated whole system. Therefore, whoever specifies this type of relay should also provide the settings and coordination curves as part of the design package to show that he knew what he was doing when selecting their use. This very important task should not be left to others and once set, the settings must not be tampered (even by the operating staff ) as otherwise coordination is lost.
Minimum Grading Intervals
To engineers planning the protection for a medium- to low-voltage network and wishing to adopt the widespread use of the IDMT OCEF relay, the above can be summarized as follows:
Design networks with a minimum number of grading levels possible.
Choose CT ratios based on fault current – not load current.
Consider using 1 A secondary.
Check CT magnetization curves for knee-point voltage and internal resistance.
Connect ammeters, etc. onto own metering cores.
Provide relay settings and coordination curves as part of the design package.
Be careful when choosing relay plug tap setting on electromechanical relays. The lower the tap, the higher the burden.
Relays should not pick-up for healthy conditions such as permissible transient overloads, starting surges and reconnection of loads, which have remained connected after a prolonged outage.
Care should also be taken that the redistribution of load current after tripping does not cause relays on healthy circuits to pick-up and trip.
HV IDMT relays on transformers should trip both HV and LV breakers.
Normal inverse curves should not be selected for overload protection. Rather use the inverse characteristic for this duty.
Take advantage of the additional features offered by the modern electronic relays, e.g. fixed very low burden, integral high-set, breaker fail and busbar blocking protections, event memory, etc. However, remember, one has to do the same calculation exercises for settings and draw coordination curves whether the relays are of the electronic or electromechanical design.
Finally, if the switchgear suppliers also manufacture relays, do not expect them to do the protection application settings free of charge as part of the service. If this is required, specify this as a separate cost item in the specification.
Many problems down the line can be avoided and the performance, efficiency and safety of the plant improved if a protection engineer is included in the design team, if not full time, but at least to do an audit on the proposals. Finally, remember – while IDMT relays are the most well known and the cheapest, they are in fact the most difficult relays to set.
Practical Power System Protection | Download
Les Hewitson
Mark Brown PrEng, DipEE, BSc (ElecEng), Senior Staff Engineer, IDC Technologies, Perth, Australia
Ben Ramesh Ramesh and Associates, Perth, Australia
Series editor:
Steve Mackay FIE(Aust), CPEng, BSc (ElecEng), BSc (Hons), MBA, Gov. Cert. Comp., Technical Director – IDC Technologies.
Fault Analysis power system protection
Basic Guide for Power System Protection
A power system is not only capable to meet the present load but also has the flexibility to meet future demands. A power system is designed to generate electric power in sufficient quantity, to meet the present and estimated future demands of the users in a particular area, to transmit it to the areas where it will be used and then distribute it within that area, on a continuous basis.
"To ensure the maximum return on the large investment in the equipment, which goes to make up the power system and to keep the users satisfied with reliable service, the whole system must be kept in operation continuously without major breakdowns".
Read: What is the Importance of X/R Ratio?
Basic Requirements of Power System Protection
A protection apparatus has three main functions/duties:
Safeguard the entire system to maintain continuity of supply
Minimize damage and repair costs where it senses fault
Ensure safety of personnel.
These requirements are necessary, firstly for early detection and localization of faults, and secondly for the prompt removal of faulty equipment from service. In order to carry out the above duties, protection must have the following qualities:
Selectivity: To detect and isolate the faulty item only.
Stability: To leave all healthy circuits intact to ensure continuity or supply.
Sensitivity: To detect even the smallest fault, current or system abnormalities and operate correctly at its setting before the fault causes irreparable damage.
Speed: To operate speedily when it is called upon to do so, thereby minimizing damage to the surroundings and ensuring safety to personnel.
To meet all of the above requirements, protection must be reliable which means it must be:
Dependable: It must trip when called upon to do so.
Secure: It must not trip when it is not supposed to.
Important Points to Consider in Protection System
Protection of any distribution system is a function of many elements and this manual gives a brief outline of various components that go into protecting a system. Following are the main components of protection.
Fuse is the self-destructing one, which carries the currents in a power circuit continuously and sacrifices itself by blowing under abnormal conditions. These are normally independent or stand-alone protective components in an electrical system unlike a circuit breaker, which necessarily requires the support of external components.
Accurate protection cannot be achieved without properly measuring the normal and abnormal conditions of a system. In electrical systems, voltage and current measurements give feedback on whether a system is healthy or not. Voltage transformers and current transformers measure these basic parameters and are capable of providing accurate measurement during fault conditions without failure.
The measured values are converted into analog and/or digital signals and are made to operate the relays, which in turn isolate the circuits by opening the faulty circuits. In most of the cases, the relays provide two functions viz., alarm and trip, once the abnormality is noticed. The relays in the olden days had very limited functions and were quite bulky. However, with the advancement in digital technology and the use of microprocessors, relays monitor various parameters, which give a complete history of a system during both pre-fault and post-fault conditions.
The opening of faulty circuits requires some time, which may be in milliseconds, which for a common day life could be insignificant. However, the circuit breakers, which are used to isolate the faulty circuits, are capable of carrying these fault currents until the fault currents are totally cleared. The circuit breakers are the main isolating devices in a distribution system, which can be said to directly protect the system.
The operation of relays and breakers require power sources, which shall not be affected by faults in the main distribution. Hence, the other component, which is vital in the protective system, is batteries that are used to ensure uninterrupted power to relays and breaker coils.
Basic Components of Power System Protection
Read: What are the Conditions in Selecting Current Transformer in Protective Relaying?
Voltage transformers and current transformers: To monitor and give accurate feedback about the healthiness of a system.
Relays: To convert the signals from the monitoring devices, and give instructions to open a circuit under faulty conditions or to give alarms when the equipment being protected, is approaching towards possible destruction.
Fuses: Self-destructing to save the downstream equipment being protected.
Circuit breakers: These are used to make circuits carrying enormous currents, and also to break the circuit carrying the fault currents for a few cycles based on feedback from the relays.
DC batteries: These give uninterrupted power source to the relays and breakers that are independent of the main power source is protected.
Related Articles: Fault Analysis
Practical Power System Protection | Chapter 1: Need for Protection | Download
Electrical Machines Transformer
What are the Basic Characteristics of an Ideal Transformer?
Substation Transformer
A transformer is an electrical piece of equipment that transforms the AC electrical power from one circuit to another. It makes use of the magnetically coupled coils to transfer energy.
Basically, it consists of a primary winding and secondary winding. The primary winding and its circuit are called the Primary Side of the transformer. The secondary winding and its circuit are called the Secondary Side of the transformer. Both the primary and the secondary winding of a transformer are electrically isolated from each other, but they are linked through the magnetic field.
How to Calculate Transformer Voltage Drop
How to Develop Zero- Sequence Network of Transformer?
Therefore, the primary and the secondary windings are magnetically coupled to each other. If the primary is connected to an alternating voltage source, an alternating flux is produced. The mutual flux will link the other winding (the secondary) to the primary and will induce a voltage in it. If the secondary winding is open (not connected to a load), the current in the primary winding is determined by its inductive.
The Ideal Transformer
An ideal transformer is a perfect transformer in which there is no power loss. In an ideal transformer:
The windings are purely inductive with no resistance. Therefore, there are no copper losses in the windings.
The iron core would not heat up during operation. Therefore, there are no losses in the iron core.
The magnetizing current is zero, the current flow in the primary winding is zero when the secondary winding is open circuit.
Ideal Transformer
Transformer Turns Ratio in an Ideal Transformer
The magnetic flux is the same through the primary and the secondary windings.
Therefore, the induced voltage per turn is the same in both the primary and the secondary.
That means, Ep and Es are proportional to NP and NS respectively.
The Basic formula of an Ideal Transformer
From the given formula we can say the following:
If VP > VS the voltage is stepped down from a higher voltage to a lower voltage the transformer is then called a step-down transformer.
If VP < VS, the voltage is stepped up from a lower voltage to a higher voltage, and the transformer is then called a step-up transformer.
By interchanging the connections of the primary and the secondary windings, a step-down transformer can be made a step-up transformer.
In the figure shown below, determine the following:
a. the secondary voltage
b. the secondary current
c. the primary current
d. the power in the load
a. From the given formula, we can say Vp/Vs = 3/1. Thus Vs = 20.
b. By ohms law, I = Vs/ R = 20/200; Is = 100 mA
c. From the formula, Vp/Vs = Is/Ip; Ip = Vp/Vs x Is = 1/3 x 100 mA; Is = 33.3 mA
d. Power flow in the load = Vs x Is = 20 x 100 mA; Pload = 2 Watts.
BS7671 Electrical Design Electrical Installation Voltage Drop Calculation
Voltage Drop in Consumer Installations According to BS 7671
Voltage drop in a consumer's installation can be a contentious issue. However, it is an important aspect of installation design since if it is too high some certain equipment will not function correctly or will not function at all.
Rules Applied:
525.1 In the absence of any other consideration, under normal service conditions the voltage at the terminals of any fixed current-using equipment shall be greater than the lower limit corresponding in the product standard relevant to the equipment.
525.100 Where fixed current-using equipment is not the subject of a product standard the voltage at the terminals shall be such as not to impair the safe functioning of that equipment.
525.101 The above requirements are deemed to be satisfied if the voltage drop between the origin of the installation (usually the supply terminals) and a socket-outlet or the terminals of fixed current-using equipment, does not exceed that stated in Appendix 4 Section 6.4
Calculating Voltage Drop
When calculating voltage drop due consideration should be given to the following:
motor starting currents; in-rush currents
control voltages (particularly those associated with computerized systems).
Motor control contactors and relays can 'drop out' if the coil voltages fall towards 80% of the operating voltage.
The effects of harmonic currents may also need to be considered and included in the calculation.
Voltage transients and voltage variations due to an abnormal operation can be ignored.
Read: Earthing System According to BS 7671
The maximum voltage drop values can be taken from the table shown below:
For 230 Volts Network
Allowable Voltage Drop Based on BS 7671
*The voltage drop within each final circuit on Private Networks, should not exceed the values given in (i) above for Public Networks
When calculating the voltage drop in a circuit, the design current can be taken as being either the equipment rated current or, where there are a number of loads, the total connected load multiplied by a diversity factor.
Note: If the total circuit length exceeds 100 meters, the limits given in Table 4Ab may be increased by 0.005% per meter up to a maximum of 0.5%.
The voltage drop can be apportioned throughout the system circuits as the designer wishes, but the final circuit voltage drop is limited to the values given for Public Networks, regardless of whether it is a Public Network or a Private Network.
In case that the supply voltage at the origin is lower than the nominal 230/400V, the designer needs to consider the effect of the minimum permissible supply voltage. This is a maximum of 6% below the nominal supply voltage, which equates to 216.2V (for 230 V network ) and 376V (for 400 V network) respectively.
Electrical Contractors Association Fact Sheet | Download
circuit breaker circuit breaker curve cooper bussman electric protection Electrical Design
How to Interpret the Different Region of Circuit Breaker Curves
by: EATON
Circuit breaker time-current characteristic curves are read similar to fuse curves. The horizontal axis represents the current, and the vertical axis represents the time at which the breaker interrupts the circuit. When using molded case circuit breakers of this type, there are four basic curve considerations that must be understood.
Overload Region
Instantaneous Region
The opening of a molded case circuit breaker in the overload region is generally accomplished by a thermal element, while a magnetic coil is generally used on power breakers. Electronic sensing breakers will utilize CTs. As can be seen, the overload region has a wide tolerance band, which means the breaker should open within that area for a particular overload current.
The instantaneous trip (I.T.) setting indicates the multiple of the full load rating at which the circuit breaker will open as quickly as possible. The instantaneous region is represented in the following curve and is shown to be adjustable from 5x to 10x the breaker rating. When the breaker coil senses an overcurrent in the instantaneous region, it releases the latch which holds the contacts closed.
Interrupting Rating
The interrupting rating of a circuit breaker is a critical factor concerning protection and safety. The interrupting rating of a circuit breaker is the maximum fault current the breaker has been tested to interrupt in accordance with testing laboratory standards. Fault currents in excess of the interrupting rating can result in the destruction of the breaker and equipment and possible injury to personnel. In other words, when the fault level exceeds the circuit breaker interrupting rating, the circuit breaker is no longer a protective device.
Read: What are the different types of circuit breakers and their uses?
Illustration: Medium to High-Level Fault Currents–Circuit Breakers
The following curve illustrates a 400A circuit breaker ahead of a 90A breaker. Any fault above 1500A on the load side of the 90A breaker will open both breakers.
The 90A breaker will generally unlatch before the 400A breaker. However, before the 90A breaker can separate its contacts and clear the fault current, the 400A breaker has unlatched and also will open. Assume a 4000A short circuit exists on the load side of the 90A circuit breaker.
Read: What is the advantage of using Thermal Magnetic Circuit Breaker in motor control?
The sequence of events would be as follows:
The 90A breaker will unlatch (Point A) and free the breaker mechanism to start the actual opening process.
The 400A breaker will unlatch (Point B) and it, too, would begin the opening process. Once a breaker unlatches, it will open. At the unlatching point, the process is irreversible.
At Point C, the 90A breaker will have completely interrupted the fault current.
At Point D, the 400A breaker also will have completely opened the circuit. Consequently, this is a non-selective system, causing a complete blackout to the other loads protected by the 400A breaker.
Cooper Bussman | Download
AREVA MiCom protective relaying schneider electric
How to Convert IEC 60044-1 Standard Protection Classification to IEEE Standard Voltage Rating?
MiCom P63x Protection Relay
There are a series of protection relays such as MiCom protection relays that are compatible with ANSI/IEEE CTs as specified in the IEEE C57.13 standard. The applicable class for protection is class "C", which specifies a non air-gapped core. The CT design is identical to IEC class P but the rating is specified differently.
The IEEE C class standard voltage rating required will be lower than an IEC knee-point voltage. This is because the IEEE voltage rating is defined in terms of useful output voltage at the terminals of the CT, whereas the IEC knee-point voltage includes the voltage drop across the internal resistance of the CT secondary winding added to the useful output. The IEC knee-point is also typically 5% higher than the IEEE knee-point.
Read: What are the Conditions in Selecting Current Transformer in Protective Relaying
Where IEEE standards are used to specify CTs, the C class voltage rating can be checked to determine the equivalent knee-point voltage (Vk) according to IEC.
The equivalence formula is:
Vk = (C x 1.05) + (Ksc x In x Rct)
Vk = (C x 1.05) + (100 x Rct)
Note: IEEE CTs are always 5A secondary rated, i.e. In =5A, and are defined with an accuracy limit factor of 20, i.e. Kssc =20.
Read: Types and Classes of Current Transformers According to IEC 60441
The following table allows C57.13 ratings to be converted to a typical IEC knee-point voltage:
* Assuming 0.002/turn typical secondary winding resistance for 5A CTs
MiCom
current transformer electrical protection protective relaying
Types and Classes of Current Transformers According to IEC 60441
Substation Current Transformer
The behavior of inductive CTs in accordance with IEC 60044-1 and IEEE C57.13 is specified for steady-state symmetrical AC currents. The more recent standard IEC 60044-6 is the only standard that specifies the performance of inductive CTs (classes TPX, TPY and TPZ) for currents containing exponentially decaying DC components of the defined time constant. This section summarises the various classes of CTs.
Class P Class P current transformers are typically used for general applications, such as overcurrent protection, where a secondary accuracy limit greatly in excess of the value to cause relay operation serves no useful purpose. Therefore a rated accuracy limit of 5 will usually be adequate. When relays, such as instantaneous 'high set' overcurrent relays, are set to operate at high values of overcurrent, say 5 to 15 times the rated current of the transformer.
Read: Protection Relays in Power System
The accuracy limit factor must be at least as high as the value of the setting current used in order to ensure fast relay operation.
Rated output burdens higher than 15VA and rated accuracy limit factors higher than 10 are not recommended for general purposes. It is possible, however, to combine a higher rated accuracy limit factor with a lower-rated output and vice versa.
When the product of these two exceeds 150, the resulting current transformer may be uneconomical and/or of unduly large dimensions.
Class P current transformers are defined so that, at rated frequency and with rated burden connected, the current error, phase displacement and composite error shall not exceed the values given in the table below.
Class PR
A current transformer with less than 10% remanence factor due to small air gaps for which, in some cases, a value of the secondary loop time constant and/or a limiting value of the winding resistance may also be specified.
Class PX
A current transformer of low leakage reactance for which knowledge of the transformer secondary excitation characteristic, secondary winding resistance, secondary burden resistance and turns ratio is sufficient to assess its performance in relation to the protective relay system with which it is to be used.
Class PX is the definition in IEC 60044-1 for the quasi-transient current transformers formerly covered by class X of BS 3938, commonly used with unit protection schemes.
Class PX type CTs are used for high impedance circulating current protection and are also suitable for most other protection schemes.
Class TPS
Protection current transformers specified in terms of complying with class TPS are generally applied to unit systems where the balancing of outputs from each end of the protected plant is vital. This balance, or stability through fault conditions, is essential of a transient nature and thus the extent of the unsaturated (or linear) zones is of paramount importance.
It is normal to derive, from heavy current test results, a formula stating the lowest permissible value of Vk if the stable operation is to be guaranteed.
The performance of class TPS current transformers of the low (secondary) reactance type is defined by IEC 60044-6 for transient performance. In short, they shall be specified in terms of each of the following characteristics:
Rated primary current
Turns ratio (the error in turns ratio shall not exceed ±0.25%)
Secondary limiting voltage
The resistance of secondary winding Class TPS CTs are typically applied for high impedance circulating current protection.
Class TPX
The basic characteristics for class TPX current transformers are generally similar to those of class TPS current transformers except for the different error limits prescribed and possible influencing effects which may necessitate a physically larger construction.
Read: What are the IEEE/ANSI Device Numbers Used in Power System Protection?
Class TPX CTs have no air gaps in the core and therefore a high remanence factor (70-80% remanent flux). The accuracy limit is defined by the peak instantaneous error during the specified transient duty cycle. Class TPX CTs are typically used for line protection.
Class TPY
Class TPY CTs have a specified limit for the remanent flux. The magnetic core is provided with small air gaps to reduce the remanent flux to a level that does not exceed 10% of the saturation flux.
They have a higher error in current measurement than TPX during unsaturated operation and the accuracy limit is defined by peak instantaneous error during the specified transient duty cycle. Class TPY CTs are typically used for line protection with auto-reclose.
Class TPZ
For class TPZ CTs the remanent flux is practically negligible due to large air gaps in the core. These air gaps also minimize the influence of the DC component from the primary fault current but reduce the measuring accuracy in the unsaturated (linear) region of operation.
The accuracy limit is defined by peak instantaneous alternating current component error during single energization with maximum DC offset at specified secondary loop time constant. Class TPZ CTs are typically used for special applications such as differential protection of large generators.
AREVA
Electrical Machines motor control
Star Delta Motor Starting Explained
Star Delta Power Circuit
Star Delta starting is when the motor is connected (normally externally from the motor) in STAR during the starting sequence. When the motor has accelerated to close to the normal running speed, the motor is connected in DELTA.
The change of the external connection of the motor from Star to Delta is normally achieved by what is commonly referred to as Star-Delta starter. This starter is simply a number of contactors (switches) that connect the different leads together to form the required transition from Star to Delta.
When the motor is started in the star connection, the phase voltage of the motor is reduced by a factor of √3. The reductions in starting current, starting power, and starting torques for a reduced Voltage can each be calculated by using equation 1 (This ignores other factors like saturation, etc.):
These starters are normally set to a specific starting sequence, mostly using a time setting to switch between Star and Delta. There can be extensive protection on these starters, monitoring the starting time, current, Voltage, motor speed etc.
For example, if the supply voltage is 380 Volts. During starting in which the motor is connected into Star, the impressed voltage across each coil is 380/ 1.73 which is 220 Volts. As a result of the reduction of the impressed voltage, the starting torque will also reduce to 67%.
Control Circuit
From the control circuit above, when switch S1 is pressed, there will be a complete path of electric current that will flow from L1 to L2 causing the following coils to be activated:
Read: Electric Motor Control in Industrial Plants
K1 - line or main contactor
K2 - star contactor
K4 - timer (set at 3 to 5 seconds)
After the predetermined time, there will be a transition of timer contact. As such the time delay close contact (K3)which controls the star contactor will now become open while the time delay close contact (K2) will do the opposite. In this way, the transition from star to delta is executed.
The auxiliary contact of contactor K1 is connected in parallel with the start button S1 (latched) so that the circuit will remain activated even when S1 goes back to the open position. Note that S1 is characterized by a pushbutton that will return to its original state after being pressed.
The normally closed contacts K3 and K2 are also interlocked to prevent activating STAR and DELTA connection at the same time that can cause serious damage to the motor.
What are the advantages of using Star Delta starting?
The most significant advantage of this starting method is the reduction inrush current during starting. The reduction of the starting current can also reduce the mechanical stress of motor due to high starting torque. Note that when reduce voltage starting is not applied, the starting current could reach as high as 600%.
Electrical Design Electrical Installation
What are the General Guidelines in Electrical Design?
To get the best results, an electrical engineer needs to be aware of specific guidelines so that they can identify the required information that needs to be included.
Determine the load power demands
Electrical design starts with the study of the nature of the proposed project in relation to the understanding of all codes, legislations, and standards. The total power demand can be calculated from the data relative to the location and power of each load, together with the knowledge of the operating modes such as the following:
steady state demand
starting conditions
non-simultaneous operation
Read: How To Prepare Schedule of Loads
From the obtained data, the requirements of power from the utility supply and the number of sources necessary for an adequate supply to the installation are readily obtained, as necessity arise. The local information pertaining to the tariff structures must also be sought so that we can the best option of connection arrangements will be attained.
Depending on the necessity and the size of the electrical installation, it is better to select properly the service locations.
Medium Voltage Level Service Connections - A consumer-type substation will then have to be studied, built and equipped. This substation may be an outdoor or indoor installation conforming to relevant standards and regulations (the low-voltage section may be studied separately if necessary). Metering at medium-voltage or low-voltage is possible in this case.
Low Voltage level Service Connections- The installation will be connected to the local power network and will (necessarily) be metered according to LV tariffs.
Architecture of the Electrical Distribution
The whole installation distribution network needs to be considered as a complete system. With respect to the necessity of the project, a selection guide is proposed for determination of the most suitable architecture. MV/LV main distribution and LV power distribution levels are covered. Neutral earthing arrangements are chosen according to local regulations, constraints related to the power-supply, and to the type of loads.
The distribution equipment such as switchgears, panels, MSS and other equipment must be determined from building plans and from the location and grouping of loads. The type of premises and allocation can influence their immunity to external disturbances.
Protection against electric shocks
The earthing system (TT, IT or TN) having been previously determined, then the appropriate protective devices must be implemented in order to achieve protection against hazards of direct or indirect contact.
Read: Basic Safety Provision for Electrical Installation According to BS 7671
Sizing and Protection
Every part of the electric circuit must undergo a detailed study. It starts from the calculation of the rated currents of the loads, the magnitude of short-circuit currents, and the type of protective devices, the sizes of circuit conductors, and the specification of the cable ducts and conduits. Also, anything that can affect the rating of the conductors must also be identified.
The voltage drop complies with the relevant standard
Motor starting is satisfactory
Protection against electric shock is assured
The possible temperature where the electrical system is to be installed
Earth Fault Loop
How to Select Overcurrent Protection Devices?
What is Earth Fault Loop Impedance?
The short-circuit current must is then determined in order to identify the rating of interrupting capacity of the protective devices. These calculations may indicate that it is necessary to use a conductor size larger than the size originally chosen.
The performance required by the switchgear will determine its type and characteristics. The use of cascading techniques and the discriminative operation of fuses and tripping of circuit breakers are examined.
Protection against overvoltages
Direct or indirect lightning strokes can damage electrical equipment at a distance of several kilometers. Operating voltage surges, transient and industrial frequency over-voltage can also produce the same consequences. The effects are examined and solutions are proposed.
Energy efficiency in electrical distribution
Implementation of measuring devices with an adequate communication system within the electrical installation can produce high benefits for the user or owner: reduced power consumption, reduced cost of energy, better use of electrical equipment
Reactive energy
The power factor correction within electrical installations is carried out locally, globally or as a combination of both methods.
Harmonics in the network affect the quality of energy and are at the origin of many disturbances as overloads, vibrations, ageing of equipment, trouble of sensitive equipment, of local area networks, telephone networks. This chapter deals with the origins and the effects of harmonics and explain how to measure them and present the solutions.
Particular supply sources and loads
Particular items or equipment are studied: b Specific sources such as alternators or inverters b Specific loads with special characteristics, such as induction motors, lighting circuits or LV/LV transformers b Specific systems, such as direct-current networks.
electric protection Electrical Design short circuit analysis
Why is Voltage Rating Important in Selecting Circuit Protection Devices?
This is an extremely important rating for overcurrent protective devices (OCPDs). The proper application of an overcurrent protective device according to its voltage rating requires that the voltage rating of the device be equal to or greater than the system voltage. When an overcurrent protective device is applied beyond its voltage rating, there may not be any initial indicators. Adverse consequences typically result when an improperly voltage rated device attempts to interrupt an overcurrent, at which point it may self-destruct in an unsafe manner.
There are two types of OCPD voltage ratings:
straight voltage rated and;
slash voltage rated.
The proper application is straightforward for overcurrent protective devices with a straight voltage rating (i.e.: 600V, 480V, 240V) which have been evaluated for proper performance with full phase-to-phase voltage used during the testing, listing and marking. For instance, all fuses are straight voltage rated and there is no need to be concerned about slash ratings.
However, some mechanical overcurrent protective devices are slash voltage rated (i.e.: 480/277, 240/120, 600/347). Slash voltage rated devices are limited in their applications and extra evaluation is required when they are being considered for use. The next section covers fuse voltage ratings followed by a section on slash voltage ratings for other type devices.
Overcurrents
An overcurrent is either an overload current or a short-circuit current. The overload current is an excessive current relative to normal operating current, but one which is confined to the normal conductive paths provided by the conductors and other components and loads of the distribution system. As the name implies, a short-circuit current is one which flows outside the normal conducting paths.
Overloads are most often between one and six times the normal current level. Usually, they are caused by harmless temporary surge currents that occur when motors start up or transformers are energized. Such overload currents, or transients, are normal occurrences. Since they are of brief duration, any temperature rise is trivial and has no harmful effect on the circuit components. (It is important that protective devices do not react to them.) Continuous overloads can result from defective motors (such as worn motor bearings), overloaded equipment, or too many loads on one circuit.
Such sustained overloads are destructive and must be cut off by protective devices before they damage the distribution system or system loads. However, since they are of relatively low magnitude compared to short-circuit currents, removal of the overload current within a few seconds to many minutes will generally prevent equipment damage. A sustained overload current results in overheating of conductors and other components and will cause deterioration of insulation, which may eventually result in severe damage and short circuits if not interrupted.
Whereas overload currents occur at rather modest levels, the short-circuit or fault current can be many hundred times larger than the normal operating current. A high level fault may be 50,000A (or larger). If not cut off within a matter of a few thousandths of a second, damage and destruction can become rampant–there can be severe insulation damage, melting of conductors, vaporization of metal, ionization of gases, arcing, and fires. Simultaneously, high level short-circuit currents can develop huge magnetic field stresses. The magnetic forces between bus bars and other conductors can be many hundreds of pounds per linear foot; even heavy bracing may not be adequate to keep them from being warped or distorted beyond repair.
The fuse is a reliable overcurrent protective device. A "fusible" link or links encapsulated in a tube and connected to contact terminals comprise the fundamental elements of the basic fuse. Electrical resistance of the link is so low that it simply acts as a conductor. However, when destructive currents occur, the link very quickly melts and opens the circuit to protect conductors and other circuit components and loads.
Modern fuses have stable characteristics. Fuses do not require periodic maintenance or testing. Fuses have three unique performance characteristics:
Modern fuses have an extremely "high interrupting" rating–can open very high fault currents without rupturing.
Properly applied, fuses prevent "blackouts." Only the fuse nearest a fault opens without upstream fuses (feeders or mains) being affected–fuses thus provide "selective coordination." (These terms are precisely defined in subsequent pages.)
Fuses provide optimum component protection by keeping fault currents to a low value…They are said to be "current- limiting."
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Trooper Jerry Hines was shot and killed after making a traffic stop at the interchange of I-81 and I-64, near Lexington, Virginia.
Unbeknownst to him, the male passenger had just killed the elderly owner of the vehicle and was holding the female driver as a hostage.
As Trooper Hines spoke with the female outside of the vehicle, the suspect opened fire, striking him in the neck and shoulder, killing him instantly.
The vehicle was spotted by members of the Salem Police Department, who began to pursue it. During the chase, the suspect killed the female passenger and then attempted to commit suicide, but survived.
The suspect was convicted of capital murder and executed in 1998.
Trooper Hines was a veteran of the Virginia National Guard.
On today, the 30th anniversary of your death I would just like to say thank you for your service and sacrifice-not just as a LEO but for our Country as well when you served with the VAARNG. And to your Family and loved ones, I wish to extend my deepest sympathy.


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Scientists successfully produce the sugar component of DNA under simulated astrophysical conditions.
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text:
Shots Fired Early Monday Morning in Downtown Dubuque
Ken Peiffer Published: November 27, 2017
This is the official press release from the Dubuque Police Department regarding shots fired earlier today.
On November 27th, 2017, at approximately 3:37 a.m., Dubuque Police responded to the 1800 block of Central Avenue on the report of shots fired. Upon arrival, officers located evidence indicating the exterior of Club Rise, at 1850 Central Avenue, had been damaged by gunfire. The investigation determined a disturbance developed between Club Rise management and a music promoter, Ricardo Sanchez, 32, of Chicago, regarding payment for a concert held earlier at the bar. During the disturbance, Sanchez allegedly exited the bar and retrieved a handgun from a vehicle outside. He then proceeded to fire at the building several times. No one inside the bar was injured. Sanchez then retreated back to the vehicle and fled the scene. The details above were corroborated by witnesses and traffic/security cameras in the area.
At approximately 4:24 a.m., Galena (IL) Police located the suspect vehicle in the Walmart parking lot. Sanchez was among the occupants and was placed under arrest for Intimidation with a Dangerous Weapon and Going Armed with Intent. Intimidation with a Dangerous Weapon is a Class C Felony punishable by a fine between $1,000 to $10,000, and up to 10 years in prison. Going Armed with Intent is a Class D Felony, punishable by a fine between $750 and $7,500, and up to 5 years in prison. Sanchez is being held in the Jo Daviess County (IL) Jail on a $50,000 cash bond, pending extradition to Dubuque.
As with any criminal case, the charges filed are allegations and any suspects are presumed innocent until convicted in a court of law. If you have any information on this incident or others, please call the Dubuque Police Department at 563-589-4415 or Crime Stoppers at 800-747-0117 or 563-588-0714 (if the information leads to an arrest, the caller is eligible for a cash reward of up to $2,000). You can also submit tips anonymously online at www.cityofdubuque.org/police or through the MyDBQ smartphone app available at www.cityofdubuque.org/MyDBQ.
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redpajama_set_name: RedPajamaCommonCrawl


text:
Q: Is it legal for a lambda to odr-use this or a not captured entity with automatic storage duration in C++20? [expr.prim.lambda.capture]/8 of the final draft of C++17 N4659:

An entity is captured if it is captured explicitly or implicitly. An entity captured by a lambda-expression is odr-used in the scope containing the lambda-expression. If *this is captured by a local lambda expression, its nearest enclosing function shall be a non-static member function. If a lambda-expression or an instantiation of the function call operator template of a generic lambda odr-uses this or a variable with automatic storage duration from its reaching scope, that entity shall be captured by the lambda-expression. If a lambda-expression captures an entity and that entity is not defined or captured in the immediately enclosing lambda expression or function, the program is ill-formed.

However, [expr.prim.lambda.capture]/8 of the final draft of C++20 N4861:

An entity is captured if it is captured explicitly or implicitly. An entity captured by a lambda-expression is odr-used ([basic.def.odr]) in the scope containing the lambda-expression. [ Note: As a consequence, if a lambda-expression explicitly captures an entity that is not odr-usable, the program is ill-formed ([basic.def.odr]). — end note ]

It removes the description that this or such entities should be captured in this case. Does it mean they don't need to be captured (of course, that's not possible)? Or is it explained elsewhere?

A: For future reference, I find this GitHub repository https://github.com/cplusplus/draft is useful in finding out how things changed between different C++ standards. In particular, I found this commit using git blame, which is the result of P0588R1: Simplifying implicit lambda capture (to resolve CWG 1632. Lambda capture in member initializers)
It seems that this has been moved to [basic.def.odr]p9 in N4861:

A local entity ([basic.pre]) is odr-usable in a declarative region ([basic.scope.declarative]) if:

*

*(9.1) either the local entity is not *this, or an enclosing class or non-lambda function parameter scope exists and, if the innermost such scope is a function parameter scope, it corresponds to a non-static member function, and

*(9.2) for each intervening declarative region ([basic.scope.declarative]) between the point at which the entity is introduced and the region (where *this is considered to be introduced within the innermost enclosing class or non-lambda function definition scope), either:

*

*(9.2.1) the intervening declarative region is a block scope, or

*(9.2.2) the intervening declarative region is the function parameter scope of a lambda-expression that has a simple-capture naming the entity or has a capture-default, and the block scope of the lambda-expression is also an intervening declarative region.

If a local entity is odr-used in a declarative region in which it is not odr-usable, the program is ill-formed.

(emphasis mine)
So for an automatic variable or this to be odr-usable, they need to be captured.

redpajama_set_name: RedPajamaStackExchange


text:
A Daughter, Her Dad and Their Mets »
« That Familiar Feeling
Herbie Harbinger's Home Run Hindsight
by Greg Prince on 5 April 2021 4:11 pm
What do we want out of Opening Day?
1) For it to arrive.
2) For the Mets to win.
3) For the Mets to homer.
The first is essential, whether we're talking wishing for the season to start sooner than possible (when Spring Training inevitably drags) or start at all (see 2020…or just the other day). The second speaks for itself. The third? It's just better when a Met hits a home run in the first baseball game of the year. It's not necessary to win, and it doesn't completely redeem the day if we lose, but how can you not love an Opening Day home run? The Opening Day home run is the loudest of home runs. It announces Mets baseball's presence with authority. If it's launched at the home of the Mets, the volume is deafening. If it's launched on the road, as it will have to be tonight in Philadelphia, it hollers over a crowd we wish to quiet down.
Plus, it's a home run. Home runs are highlights that don't have to be explained. Boom, as Warner Wolf liked to say.
The Mets are famous for their Opening Day record of success since 1970, going like a million and four. "Like" a million and four translates literally to 40-12, which includes the Second Season Opener of 1981 (clarifying that asterisky point is truly my OCD). In those 40 wins, sometimes the Mets didn't homer. No longballs in 2015, 2017 or 2018, to cite three recent examples of happy Opening Day recaps. Was our ebullience detracted from because we didn't blaze a path to victory four bags at a time? Not really. But "Yoenis Cespedes homered and the Mets won!" (2020) or "Robinson Cano homered and the Mets won!" (2019) is so simple, satisfying and powerful. And on a chilly Opening Day like that of March 31, 2014, losing certainly sucked, but the three Mets hit homers and that loudly if briefly raised spirits right out of the box.
You'd rather win and not homer than lose and homer a lot. You'd rather it take fourteen innings — without a runner on second to start every extra half-inning — to win on Opening Day, 1-0, with the one run poked through the infield with the bases loaded in the bottom of the fourteenth. That's how the Mets won on March 31, 1998, a.k.a. the Alberto Castillo Game, so named for the backup catcher who did the fourteenth-inning poking. No homers, no problems. The recap couldn't help but be happier than in 2014. It was also a whole helluva lot warmer.
No two March 31s are alike (except that March 31 is too early for baseball) just as no two Opening Days are alike, save for the part that Tom Boswell said about time beginning, however delayed time might find itself. This here 2021 Opening Day/Night is the ninth Mets opener that is taking place later than initially scheduled.
• In 1962, it rained in St. Louis, which was OK, because it gave the Mets extra time to emerge from their stalled hotel elevator; the Mets started existing a day later.
• In 1966, cats and dogs came down on Cincinnati, catapulting the Mets from the honor of contesting the traditional opener at Crosley field on a Monday to starting their season at Shea on a Friday.
• Two years later, in 1968, the funeral of Martin Luther King compelled baseball to push back its openers, including the Mets' at San Francisco, by a day (though the process was hardly smooth).
• The first modern in-season players' strike lopped the first week of the season off the schedule in 1972.
• Snow got the best of the Mets and Phillies at the Vet in 1982 (somehow the last time the Mets opened in Philadelphia until tonight), but the carpet got cleared off within a couple of days.
• A lockout forced the sport to scramble a bit in 1990, with openers everywhere coming almost a week late; unlike in '72, the missing April games were made up rather than simply cancelled.
• The dreaded strike of 1994 had morphed into the dreaded strike of 1995, meaning a late-April start to baseball in the latter year, touching off a shortened schedule of 144 games.
• You likely haven't forgotten that baseball in 2020 didn't begin until the end of July…or that the Mets of 2021 cooled their heels this past weekend in D.C.
So yes, start a season. And win the game. And homer! It's fun!
The Mets have hit 59 homers in their 60 openers to date (or 58 in their 59 openers to date if you insisting on being a Second Season 1981 killjoy). The Mets are 23-14 in openers when they opener and 17-6 when they don't. The presence of a home run doesn't always portend a win, and the absence of a home run certainly doesn't guarantee a loss. But as long as we're on the subject, what might an Opening Day home run mean in the long term once that first burst of fun evaporates?
For that, I turned to my friend Herbert Hindsight Harbinger to fill me in. Herbie Harbinger has splendid hindsight and can explain in great detail what something means after the fact. When not breaking down decades-old Opening Days for me, he appears regularly on several cable news channel panel shows.
Here's some of what Herbie Harbinger told me vis-à-vis Opening Day home runs as harbingers of Mets developments to come.
1) The first Mets Opening Day home run qualifies as a hellacious harbinger. It — obviously the first homer in Mets history — was hit by Gil Hodges. Gil Hodges would go on to become one of a handful of the most important figures in New York Mets history. Was managing the 1969 Mets to their world championship and winning universal acclaim for his role in molding heretofore hopeless sad sacks into kings of the baseball universe directly traceable to Gil's fourth-inning home run from seven-and-a-half years earlier? Let's say that in the telling of the Hodges Mets story, it's a fun tidbit. And we did say that home runs on Opening Day are fun.
The Mets lost their first Opening Day, 11-4, despite the homer from Hodges and one an inning later from Charlie Neal. The loss itself was more the harbinger of things to come in 1962.
2) Ron Swoboda homered on Opening Day in 1968 at Candlestick. The Mets lost. The Mets always lost on Opening Day back then. No exaggeration. Swoboda would go on to hit 11 homers in all in The Year of the Pitcher. By the title of the campaign in question, Rocky's clout clearly wasn't a harbinger of a Met power surge in general. The Mets hit 81 as a team in '68, or five fewer than the 2020 Mets hit in sixty games.
3) Duffy Dyer delivered a pinch-home run on Opening Day 1969. It couldn't have been more dramatic. There were two outs, there were two on, it was the bottom of the ninth inning, and Duffy's blast put the Mets…one behind the newborn Expos. All right, so it could have been more dramatic. Dyer's homer ramped up the Mets' attack impressively, but they went from losing, 11-7, to losing, 11-10, which is what they lost by. Ol' Duff would hit two more homers all year and the Mets would lose only 61 more times, so you might say this shot, no matter how exhilarating in the moment, was as unharbingery as imaginable.
Yet exhilarating just the same.
4) Ed Kranpeool's home run in the strike-delayed 1972 opener represented a milestone, marking the first time a Met ever homered in a Mets Opening Day win. It only took eleven Opening Days for the two events to coincide. As with chocolate and peanut butter, you didn't ask the Reese's folks what took so long to put them together. You just enjoyed that they had combined forces and you asked for more.
5) On Opening Day 1973, Cleon Jones went deep not once but twice, the first time a Met had homered more than once on Opening Day. Four Mets would do the same on later Opening Days, also sparking wins. And Cleon would do it again on September 19, homering twice to help pulverize Pittsburgh en route to the Mets swiping first place out from under the Buccos. Herbie Harbinger casts Cleon's moves as excellent foreshadowing.
6) It's 1975! Dave Kingman has arrived! And homered on Opening Day! He's going to hit 36 this season! He's going to set the franchise record! Herbie Harbinger — having brought his kiddies, brought his wife — is hollerin' and cheerin' and jumpin' in his seat because there was, at last, a Met really sockin' the ball.
7) It's 1979. Richie Hebner has homered on Opening Day. And we all remember both the season and the player's production therein as sexy. Or the farthest thing from it. But on Opening Day 1979, as Rod Stewart had been noting on the radio in the weeks prior, who right here was complaining?
8) The Mets didn't homer on Opening Day 1980. The Mets homered hardly at all in 1980, knocking those home runs over the wall 61 measly times. Who right here was complaining about this, either? It was still fun to win on Opening Day and it was definitely fun to change ownership before Opening Day.
9) The first Mets Opening Day of 1981 featured home runs from two different Mets on Opening Day for the first time since the first Mets Opening Day at all in 1962. Filling the shoes of Messrs. Hodges and Neal nineteen years later were Lee Mazzilli and Rusty Staub. The Mets would win the game in Chicago, then lose a lot of games for a couple of months, then go on strike with their colleagues. Herbie isn't impressed.
10) The second Mets Opening Day of 1981, introducing the split season concept to a grateful nation (well, me), featured a home run from Kingman, who, like Staub, was a Recidivist Met that year(s). Sky had fourteen before the strike, eight after. Herbie Harbinger wishes he'd hit a few more following the split.
11) Snow week in Philadelphia in 1982 culminated in something the Mets had never done in the City of Brotherly Love and surfeit of live shots of cheesesteaks sizzling in Philadelphia on SNY (though those would air later). Joe Christopher had homered at Connie Mack Stadium on Opening Day 1964, but the Mets lost. No Met homered on Opening Day at Veterans Stadium 1974, and the Mets lost. Here in the ballpark with the jail and the recently revealed secret apartment, the Mets did everything we wanted them to do. They won an opener in Philadelphia and one of them homered. Even better, the homerer of the day was George Foster, who was acquired that February exactly for this purpose.
It wasn't much of a harbinger. Even still.
By the by, how odd is it that the Mets haven't opened a season in nearby Philadelphia in 39 years and are doing so this year only because the Nationals couldn't control their COVID tests? We play the Phillies nineteen times annually most seasons. We've played in the same division since 1969. How have we not been scheduled to start our year there since 1982?
As potential near-term harbingers go, the Mets set a franchise record for most home runs in one game at Citizens Bank Park with seven in 2005, and broke that record with eight home runs in one game in 2015 in the same red-bricked facility. In the past two seasons, the Mets have homered at least once in fourteen of their past sixteen visits to CBP covering 2019 and 2020. So?
So maybe bet the homer over tonight.
12) Tom Seaver returned to the Mets in 1983. The Mets won without homering — and, as every Mets triviot knows, with Mike Howard singling in the winning run on what turned out to be his final swing in the major leagues.
But you had us at Tom Seaver returned to the Mets.
13) The Mets got blown out of Riverfront Stadium on Opening Day 1984, finally getting that honor they were rained out of at Crosley in 1966. They lost, 8-1. Some honor. Ah, but in the second inning, in his first Opening Day plate appearance, reigning National League Rookie of the Year Darryl Strawberry homered to right. It was the 27th of a career that would see 252 launched in Met threads and 335 in all. Herbie says that's pretty Harbingeriffic.
14) Gary Carter won Opening Day 1985 with his first Met home run, struck in the tenth inning off former Met Neil Allen. Gary Carter would hit 32 home runs in 1985, 24 more in 1986 and a couple in the World Series, which the Mets won. Herbie's still kvelling from Gary Carter.
15) No homers for the 1986 Mets on Opening Night in Pittsburgh. A win, but no homer. In 1969, you'll recall, they had a homer, but no win. Therefore, we can safely say that the Mets have never managed to homer in their opener; win their opener; and win the World Series in the same season. This season would be a fine season to change that fact. Or just win the World Series.
16) What's that Darryl's doing on Opening Day 1987? Swatting a three-run homer in the first inning, leading the Mets to a 3-2 win on a day that would have otherwise been a monumental drag given Dwight Gooden's drug suspension? And what was that Darryl would do before the season was over? Hit 39 home runs for a new Mets record? Herbie Harbinger approves.
17) SIX HOME RUNS ON OPENING DAY IN MONTREAL! TWO FOR DARRYL, INCLUDING ONE THAT FLEW TO THE ARCTIC CIRCLE! TWO FOR McREYNOLDS! METS WIN! DARRYL TIES HIS FRANCHISE HR RECORD! METS GO 100-60! UPPER-CASE HARBINGER ALERT!!!!
18) Howard Johnson quietly hits a home run as part of a 1989 Opening Day win at Shea. Howard Johnson quietly goes on to hit 36 home runs that season. Howard Johnson quietly made a lot of noise as a New York Met. Herbie heard him.
19) Hojo would do it again on Opening Day 1990, and he'd be joined by starting catcher Barry Lyons. We're going to be quiet about Hojo because Lyons is the anti-harbinger here because the Mets would demote Barry in the middle of the year and release him in September. Guy hits a homer on Opening Day and he doesn't last the season. In a sense Barry became a harbinger, because he became the first of three Mets to homer on Opening Day yet be sent packing before long. Oh, and the Mets lost, so all in all not the most unblemished of memories for Barry Lyons.
20) Bobby Bonilla homered twice on Opening Night in St. Louis in 1992, including mashing the game-winner in the tenth, validating the enormous contract the Mets gave him as a free agent the previous winter. Obviously everything's going to work out great between the Mets and Bobby Bo.
21) Bobby Bo homers in the Mets' win over the inaugural Rockies at Shea in 1993. See? Told you it was all going swimmingly.
22) The wind's blowing out at Wrigley on Opening Day 1994. It's certainly at the back of Jose Vizcaino, Todd Hundley and Jeff Kent, each of whom homer and contribute to a rousing Mets win. The season would be truncated in August by that nasty strike, but all three players had many years in front of them, with Hundley and Kent having many home runs in front of them. Herbie votes yea that this game was a Harbinger, even if Kent would be powerful mostly for other teams.
23) On Opening Day 1995, Rico Brogna hits the first homer ever to ever exit Coors Field. You know, I do believe other homers have flown out of that park since.
24) Hundley, who homered at Wrigley on Opening Day 1994 and Coors on Opening Day 1995, homers at Shea on Opening Day 1996 to commence an epic comeback over the Cardinals. Todd is the OD OG, eh? Not only that, but he winds up breaking Strawman's single-season franchise mark in 1996. And not only that, but Bernard Gilkey homers for the first of thirty times this season and Rey Ordoñez makes that breathtaking throw home from his knees, hinting at what kind of shortstop he's going to be.
The Mets win, which is not a harbinger for 71-91 1996, however.
25) Todd is back at it in 1997, homering on Opening Day for the fourth season in a row, this time at San Diego. He's gonna hit 30 this year, which is great. And the Mets are going to win 88 games and compete for the Wild Card, which is even better.
Never mind that Pete Harnisch and a hundred relievers give up eleven Padre runs in the sixth (only one of those numbers is an exaggeration). A new era is at hand. Sadly, it will have little to do with Todd Hundley, but you can't have everything.
26) No Hundley on Opening Day 1998, which is why we had Tim Spehr starting and Bambi Castillo heroing if not homering in the aforementioned 1-0 thriller. Maybe the Mets will have another catcher who can homer soon.
27) Beautiful John Olerud homers on Opening Day 1999 in Miami. The Mets lose. But John Olerud is always beautiful. So will be 1999.
28) Say, the Mets got that power-hitting catcher, Mike Piazza. He homers in a Met loss on Opening Day 2000, but it's in Japan, so that must count for something extra.
29) Piazza homers on Opening Night 2001 in Atlanta, which you'd figure would be the big story considering the era we're in where we hate the Braves (kicking off a bandwagon that's gathering steam of late), but it would be Robin Ventura who'd steal the home run thunder by blasting a pair. One of them is off John Rocker to take a lead in the eighth, the other is off Kerry Ligtenberg to win the game in the tenth. As for it being a harbinger, I had to admit to Herbie that I walked around the next day convinced 2001 was going to be another 1986.
Herbie chuckled at my youthful naïveté of twenty years ago.
30) Jay Payton homered as part of a balanced Met attack that vanquished Pittsburgh on Opening Day 2002. The Mets spun that 1-0 start into Wild Card contention gold (gold, Jerry!) by the end of July. So shimmering were the Mets' chances in the eyes of Steve Phillips that the GM pulled a Barry Lyons and dispatched Payton off the team. Jay was sent to Colorado where he discovered players could still hit home runs out of Coors Field and hence thrived. The Mets got in exchange for Payton John Thomson, a pitcher who was not part of a fierce Wild Card charge. Actually, the Mets stormed off in the other direction. I mean really in the other direction. Like not winning a single game at Shea Stadium in August. And Thomson, who didn't help, left as a free agent and said some grouchy things about not wanting to pitch here. Herbie couldn't bear to track down exact quotes.
31) Kaz Matsui homered on the very first pitch he saw in North American in 2004, an Opening Night win at thoroughly unmourned Turner Field. It wasn't a harbinger of a very good Met career, but it was a harbinger of what Kaz Matsui would do on first pitches he saw during the next couple of seasons to come.
32) Matsui homered. Carlos Beltran homered. Cliff Floyd homered. Pedro Martinez was dynamite. The Mets lost Opening Day 2005 at Cincinnati anyway. It wasn't a harbinger and, despite the fireworks, it wasn't that much fun.
33) In 2006, David Wright hits his first Opening Day home run in his second Opening Day. David Wright participates in his first Opening Day win. Herbie hasn't checked the archives, but I assume David Wright said something to the effect of the home run is nice and all, but the important thing is we won…which is why we loved, love and will always love David Wright.
34) One Met homers on Opening Day 2009 after all Mets skip the Opening Day four-base course for a couple of years. The Met who homers is Daniel Murphy. He'll hit twelve all year. He'll lead the Mets. Get a sense of what kind of year 2009 is going to be?
35) David contributes another homer to another victory on Opening Day 2010. He's going to hit 29 this year, a very nice change of pace after plunging to 10 in 2009. The year won't be very good for the Mets, but Wright is back! Herbie hasn't checked the archives, but I assume David said something to the effect of home runs still being nice, but winning…and so on. Still love ya, Captain!
36) Collin Cowgill ices Opening Day 2013 with a grand slam that everybody at Citi Field, no matter how raucously we greet its materialization, understands is a harbinger of absolutely nothing. He's Collin Cowgill. We know he's another Tim Spehr, except in the outfield. We're shocked that he isn't released by the time we climb the steps to the 7. We can be knocked over with a feather when he's shipped off to Lyons-Payton territory, traded to the Angels in June.
37) Andrew Brown takes Stephen Strasburg over the wall in the first inning on Opening Day 2014. Strasburg makes it safely back. Brown disappears soon enough. Herbie says he saw it coming.
38) The Mets don't homer for four consecutive Opening Days from 2015 through 2018, winning three of them. On Opening Day 2019, new Met Robinson Cano homers at Nationals Park, where the Mets really need to stop scheduling openers. Cano convinces nobody that this is a harbinger of a superb season ahead.
Cano, despite a decade or two remaining on his contract, will not be available tonight in Philadelphia. Or anytime this year.
39) Yo! He's back! For a minute, anyway, appropriate enough for a season that barely lasts half an hour, even if every games runs about 4:23. Mr. Cespedes missed all of 2019 but he was on hand to DH at Citi Field on Opening Day 2020, July 24, in front of no fans (tell me you saw those specs coming a year-and-a-half or so ago). Everything was weird during the last Opener we played, except for Jacob deGrom dealing and Yoenis Cespedes slugging. Then Yo, like the 2021 All-Star Game, hoofed it out of Atlanta and, before somebody could Barry Lyons him, opted out of 2020. Herbie insists the whole thing was a bizarre dream.
40) "Whatever you think is going to happen during the season is definitely not going to happen. Or at least not in the exact way you think. Opening Day is fun and exciting and might be a sign of things to come. Or it might just be a snapshot of how people play in April when it's mostly too cold to function."
That's not from Herbie Harbinger. That's from ex-Met Ty Kelly, writing for the Metropolitan newsletter. It's a pretty good take and from a real person. Ty made one Opening Day roster as a Met, in 2017, the same season another real person, Stephanie Pianto, wouldn't miss Opening Day for anything.
Ty Kelly can continue to lay claim to the most recent base hit in Met postseason history, one of very few the Mets garnered versus Madison Bumgarner in the 2016 Wild Card Game. I'm sure Ty won't mind if he knows we're rooting for somebody to take that distinction away from him in about six months.
41) Let's end the way we've begun so many Mets Opening Days, with 41. Tom Seaver never hit a home run on Opening Day. He didn't have to. But maybe tonight somebody wearing a patch commemorating Tom's unparalleled impact as a Met will homer and we'll win and we'll be on our way to genuinely Terrific things.
Or, as Ty suggests, it might just be a snapshot. Write down the stats, though. It'll last longer.
2 comments - (Comments closed) | | Print This Post | Citizens Bank Park, Harbingers, hindsight, Home Runs, Opening Day, Opening Day Delays, Team History
2 comments to Herbie Harbinger's Home Run Hindsight
Left Coast Jerry
April 5th, 2021 at 11:34 pm
I was at #25, the horror in San Diego. After Harnisch melted down, he was followed by the Mets debut of the Flammable Four, Yorkis Perez, Toby Borland, Barry Manuel and Ricardo Jordan. Yeesh!! I just hope the debuts tonight by Trevor May and Aaron Loup doesn't become a pattern and make them the Torchable Two.
April 6th, 2021 at 5:21 am
I guess they can always be cowgilled.
…or spehred.


Sunk on 15 April 1940 in the Norwegian Sea north-east of Harstad, in position 68.53N, 16.59E, by depth charges from the British destroyers HMS Fearless and HMS Brazen. 1 dead and 41 survivors.
After being attacked by a British aircraft the boat dived to 160m (525 ft). Minor damage.
The wreck was located on 3 March 1993 by the Norwegian submarine Skolpen. The boat is lying at a depth of 300 meters.
Unlike many other U-boats, which during their service lost men due to accidents and various other causes, U-49 did not suffer any casualties (we know of) until the time of her loss.
That boat was launched from its shipyard on 26 Nov 1915 and commissioned into the Imperial Navy on 31 May 1916. The Naval war in WWI was brought to an end with the Armistice signed on 11 Nov, 1918. Read about SM U 49 during WWI.


By mid-winter in New York, Erin and I are always ready to get out of town to someplace warm and sunny. This year, we used Kayak's "explore" function to find a cheap, tropical destination and lo-and-behold, we bought flights to Grand Cayman. The next step was finding a place to stay: after a bit of research, we decided on the Wyndham Reef Resort, on the East side of the island, away from the main tourist strip of Seven Mile Beach.
Flying to Grand Cayman was easy, JetBlue actually flies direct from New York! We rented a car since we were going to the other side of the island and wanted the flexibility. Since the island is a British territory, it was my first time driving on the left hand side of the road - I didn't make TOO many mistakes! As we drove across the island from the main city of George Town to the east side, it was nice to see the landscape change to more of a local feel. After a quick stop for a late lunch (or early dinner?) at great local spot called Kurt's Corner, we arrived at the Wyndham Reef.
As one of only a few resorts on the East side of Grand Cayman, the Wyndham felt like a little tiny village in itself. It has a huge stretch of beach, multiple pools & hot tubs, a spa, coffee shop, a restaurant, and of course a beach bar with awesome bartenders. Also, literally EVERY room looks out on the ocean. We had coffee on our balcony the first morning, enjoying the gentle sea breeze and waking up. We also stocked up on snacks & drinks at the stores right across the road which was majorly convenient.
There were a ton of available activities, and we quickly signed up for a trip to Sting Ray City. We also wanted to do a few dives, but as it turns out, since we hadn't been on a dive in 2 years we needed to do a refresher course and opted not to because of our limited time. At sunset every day, you can feed the giant Frigate birds that circle overhead from the pier, definitely a crazy experience and it seemed like kids and adults were loving it.
Happy hour was, of course, our favorite time, and we got to know the bartenders, Nazeer & Tony really well. They're both masters of the tropical cocktail, with any number of flavors possible. We were also lucky enough to be visiting during a full moon, and there's nothing quite like enjoying fresh seafood on a beach by the light of the moon! Even though we didn't take advantage of it, the resort also offers all-inclusive packages to make things simple and easy.
Hands down one of our favorite things we did was Sting Ray City. The concierge advised us to try the 7am trip, and avoid the crowds that amass by midday from the cruise ships. True to the advice, we were the ONLY boat out there, and had the entire sand bar to ourself! Plus, as a photographer, I wasn't going to say no to sunrise photos.
Our captain from White Sand Water Sports showed us how to feed the rays using squid - it was a little scary at first, but they don't have any teeth and are quite gentle. After the feeding, we had time to go snorkeling on the nearby reef as well, and it was full to the brim of sea life of all kinds.
As it turns out, 4 days on Grand Cayman was exactly what we needed to recharge our batteries. Although I might need to spend some time at the gym after too many conch fritters and piña coladas, it was a perfect, laid-back, relaxing getaway.
The Wyndham Reef kindly offered us a complimentary stay, but all opinions are my own.
When taking an airplane to an island in the middle of the Caribbean it only makes sense to then take an even smaller airplane to an even smaller island, right? When we heard how easy it was to fly out to the island of Culebra from San Juan, we were intrigued. When we found out Culebra was home to one of the top 10 beaches in the world, we were hooked.
Although the plane flight isn't for the faint of heart, the views over San Juan and the island make it worth it.
Once on the island, it's easy to rent a jeep, golf cart or scooter to toodle around the island. We opted for the golf cart, though my wife looked longingly at the scooters. We spent an entire day out at Playa Flamenco, which besides being absolutely incredible, is also home to old US Army tanks that had been abandoned and lovingly graffitied with colorful designs.
There are plenty of small restaurants and bars to get your island drinks, but we fell in love with Zaco's Tacos. The tacos were delicious, the drinks were cheap, and the bar had some killer light.
Culebra was probably the highlight of our trip, and I wish we'd had more time to relax, maybe even scuba dive. Oh well, with how easy this whole trip was, I know there's going to be a next time.
¡Hasta el proximo, Puerto Rico!
One of the many awesome things about living in New York is how easy it is to visit Puerto Rico. I don't know why, but it seems like plane flights are always dirt cheap and its status as a US territory makes things even easier. It's amazing that in the middle of a cold, NY winter you can hop a three hour flight and be in the Caribbean where your phone still works and everyone takes US dollars.
We spent our first day in Old San Juan, noted for it's colorful, colonial architecture, and giant military forts along the sea. We wandered the streets with no specific plan, stopping in coffee shops, saying hi to the alley cats, and enjoying the sea breeze.
My next post will focus on our next few days in between, but we spent the last day in the newer part of San Juan, Condado, where the luxury hotels tower over white sand beaches and the iguanas hang out with you poolside while you sip your piña coladas. Not a bad way to say goodbye!
Thanks to Leica for lending me the D-Lux camera for the trip. It was the perfect travel camera!
Stay tuned for tomorrow's post where we visited one of the top three beaches in the world!


A family launched legal action against the operators of two care homes after 76-year-old Christina Bretton's health deteriorated rapidly following admission.
She was also found to be severely dehydrated after being taken to hospital from the care home.
Hudgell Solicitors' medical negligence and care home neglect claims specialist Michelle Tebbutt represented the family of Mrs Bretton and, after investigations into the care provided, alleged that the initial care home she had been placed had not been suitably equipped to care for a resident with dementia.
It was alleged that Mrs Bretton was not assessed as being at a high risk of dehydration or nutritional loss, and that staff failed to intervene when it became obvious she was not eating and drinking sufficient amounts.
It was also alleged the pressure sores had developed in her short time in the care homes.


text:
James E. Holmes
Aurora theater shooting victims fought for this bill and now it's law: Colorado victims now must be told where out-of-state inmates are locked up
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Seeing your pet bolt through an open door is terrifying, especially if he isn't wearing a collar or identification tags. But even with identification tags, which can fall off or be removed, many pets who become lost are never reunited with their owners. Microchips can help.
Microchipping provides a permanent identification source for your pet. A microchip is about the size of a grain of rice and is inserted under the skin. If your pet becomes lost and someone finds him and takes him to a veterinarian or animal shelter, he will be scanned for a microchip. The chip will provide a number unique to your pet. Many different types of animals can be microchipped, including cats, dogs, horses, and ferrets.
Does a veterinarian have to insert a microchip?
While not necessary, it is highly recommended to have a veterinarian insert a microchip. A veterinarian will ensure that the microchip is inserted properly between the shoulder blades. Plus, veterinarians have plenty of experience handling needles safely and correctly around pets. There are many low-cost microchip clinics conducted by animal shelters and rescues to help every pet receive a microchip. Most of these clinics have veterinary professionals placing the chips, or they are comfortable with their level of experience in providing this procedure.
A common misconception is that microchips offer GPS tracking services. Unfortunately, that is not the case. A microchip only works if someone picks up your pet and takes him to a shelter or clinic, where he is scanned for the chip number. Once that chip number has been read, they can contact the company who made the chip for the registration information to find the owner. If the person who finds your pet decides to keep him, a microchip will not help you be reunited.
How does a microchip help get my pet home?
If your pet goes missing, he must be picked up and taken to a facility that has a microchip scanner (e.g., a veterinary hospital or animal shelter). Your contact information will be provided by the microchip company linked to your pet's microchip. The most important part of microchipping a pet is providing up-to-date registration information. If you ever move or change your phone number, you must remember to update your contact information with your microchip company. Otherwise, your pet's microchip will be useless.
August 15 was Check the Chip Day, which serves as a reminder to ensure your pet's microchip registration is up to date.
What other ways can I help my pet return home?
Microchips are just one component of your pet's identification system. Always make sure your pet's collar includes appropriate identification tags. Verify that your pet's ID tags have your most current phone number, and ensure that your listed phone number has a voicemail feature that is set up properly.
Number and type of pets — A pack of hunting dogs will need a much different GPS system than a single housecat.
Waterproof capabilities — Will you be hiking with your pet around ponds and streams? Or, are you simply looking for peace of mind while your pet is staying with your friends?
Scanning by strangers — QR code tags can tell the person who picked your pet up key details, such as your contact information, your pet's allergies and medications, and the vaccination status of your pet.
Subscription fees — Some trackers require monthly fees for using their satellite services. Other fees may include text and data charges.
Real-time mapping — Have you ever watched a dog in pursuit of a squirrel? He can quickly cover a lot of ground! Having the capability of a map that is updated instantaneously is crucial in finding your pet.
Battery life — If they have a short life, batteries can be the bane of even the fanciest technology. If your pet is missing for an extended period of time, you want to be sure that the battery life on the tracker will hold out until you can find your pet.
There are numerous ways to help your missing pet return home. If you'd like to get your pet microchipped for an extra layer of security, call our office at 772-283-0920.