For all my few readers – and a special thank you for all the insightful comments I received this past year.
A couple years back we had to add a UL489 circuit breaker to one of our machines.Â I ended up choosing the Weidmuller 9926 series because it was DIN rail mount, compact (only 26mm wide for double pole), affordable, and readily available.Â The 9926 worked fine in the original machine, which had a fixed panel for the electrical components.
Then another customer required a UL489 circuit breaker in our smaller machine, where the electrical equipment is mounted in a slide-out drawer.Â I made the easy decision, and specified the 9926 series again.Â Â When the first new machine was assembled, the technician noticed that if he hit the side of the electrical drawer, the circuit breaker would trip.
So we did some moreÂ testing and verified a bit ofÂ mechanical shock would cause the 9926Â to trip to the OFF position.Â However, when the electrical drawer was retracted, it was hard to get the circuit breaker to trip, so we didn’t change the circuit breaker.Â But I still wasn’t comfortable with the possibility of shock-induced trips, so I looked at other circuit breakers.
I choose because the ABL Sursum UL series from Altech because the price was within reason, I was able to get a sample to test, and they were impervious to shock.Â The Altech L series were better than the Weidmuller 9926, but I could still get them to trip via hitting them.Â Then I had the challenge of finding space, because the DIN Rail was full, and the ABL UL series was 10mm wider than the 9926, which I solved by finding a narrower power supply.
On my last trip to Excess Solutions, they had a large selection of DIN rail circuit breakers; I couldn’t resist testing them to see how shock sensitive they were; all the ones I tested passed, including models from ABB, Eaton, and Merlin Gerin.
Final note: the 9926 series has several pluses, including compact size and competitive price, and we haven’t heard of any problems with them in our machines in the field, but they aren’t a good choice for high vibration environments or other places where they might receive mechanical shock.
I’ve recently moved back to DSL since WiMax is going away.Â I’ll have some more notes about my DSL service in the future, but today it’s all about how much my apparent DSL speed can vary, based on running a variety of speed tests.
However, when I tried an old but still usable Acer A500 Android 4.0 tablet with the modem’s WiFi, speeds dropped to ~3.0 Mb/sec with a weak wireless signal, and ~8 Mb/sec with a good signal.
The A500’s speed with my longer range but slower Netgear WNR1000 via a set of NetgearÂ 85Mb/sec NetgearÂ powerline modemsÂ is pretty consistent at ~6 Mb/sec; the T100TA clocks in at 7Mb/sec.Â I suspect the bottleneck is the powerline modem.
Speeds seem pretty consistent over time when I hold the other variables (test used, PC used, connection used) constant.
BTW, my T-Mobile 4G LTE MiFi can get similar or better speeds.Â Its results vary dramatically with the signal type (LTE is much better than HSPDA, and EDGE is painful); typical download range seems to be around 8-18Â Mb/sec, and upload around 1-6 MBb/sec.Â However, despite the good raw numbers for LTE, VoIP quality is typically much better over DSL (partly because DSL still has much better ping times).Â And, of course, there are no affordable LTE options for large amounts of data, while my DSL is unlimited.
Making cables from connectors is often an adventure; today’s tale is about crimp connectors.Â I prefer crimp connectors over solder, especially trying to solder high density connectors like HD D-Sub or MDR.Â Crimp connectors are typically very affordable, and are often less fussy than IDC connectors.
However, you have to have a crimper to make a good crimp connection (duh!), and crimpers from the manufacturers can be very pricey.Â For example, a while ago we used some IMS MDrives with JST crimp connectors; the official JST hand crimper was ~$1000, so we decided to use an existing crimper (which worked OK but occasionally wasn’t good enough), and just planned on redoingÂ a significant number of crimp pins.
Sometimes crimping is impossible without the correct tool.Â I have a fewÂ cute Haydon Kerk NEMA 8 stepper motors with US Digital E4P encoders – and no encoder cables.Â The E4P uses a Molex Picoblade connector; since 100 Picoblade pins costs less than one pre-wired cable from US Digital, I decided to make my own: I bought the connector shells and 100 pins, and expected a high failure rate.
I didn’t expect a 100% failure rate – even with our smallest crimper and the help of our assembly technician, I could not get an acceptable crimp using those tiny Picoblades.Â I was defeated, but I still wasn’t going to spend my hard earned cash on a crimper that I was only going to use a couple times.
Instead, I went Excess Solutions, and looked for prewired cables with Picoblades.Â I was in luck – I found some short cables.Â Then I cut open the housing with a knife, and inserted the crimped wires into my E4P Picoblade housings.Â Success!
But since then I’ve found an even better solution: pre-crimped wires from Molex, such as the 06-66-0015 (red wire)Â or 79758-0006Â (black wire).Â One disadvantage: the wires are all the same color.
I have an Elmo servo drive with Molex Sherlock connectors, which look just slightly less devilish than Picoblades, and I’d like to use the same solution, but unfortunately I can’t find any distributors that stock the appropriate Molex parts (68801-4044 or 68801-4045).
For Molex Micro-Fit and Mini-Fit Jr, we started with the MolexÂ 64016-0201 crimper which can affordably crimp a variety of pins including Micro-Fit, Mini-Fit, KK, and CGrid.Â However, we had aÂ noticeable failure rate, and it was a little awkward, Â so we bought the dedicated crimpers for Micro-Fit (63819-0000) and Mini-Fit Jr (63819-0900).Â These crimpers are truly wonderful; it’s easy to make a good crimp with them (especially since the crimp pin is held in the correct position and orientation), and the price is reasonable considering they are made in Sweden.
I decided I wanted my own crimper that could handle Mini-Fits and such, and settled on the Hansen Hobbies Deluxe Crimper.Â Some of theÂ RC guys use the one from Servo City, which is substantially cheaper, but I felt more comfortable that the Hansen model would meet my needs.Â Later, I noticed a cheaper but similar looking model on Amazon.
It worksÂ well for Mini-Fit Jr crimp pins.
It works well for standard DSub crimp pins.
I don’t have any plans for more crimpers now, but I have to say since I do a lot of HD DSubs, the Paladin 8029Â looks sweet.Â I also might get a ratcheting ferrule crimper some day.
Some crimp pins can be inserted any way, for example, round pins such as Dsub, HD DSub, and UMNL.Â However, many pins such as Molex Mini-Fit Jr and Micro-Fit must be inserted in the correct orientation (top towards the tab I believe)Â — but when everything is done right, they go in with an easy but satisfying click!Â Sometimes all of the pins need a little push – for that I typically use a very small flat screwdriver.
Sometimes you screw up, and often you screw up worse trying to remove that pin you put in the wrong spot.
UMNL pins are easy to remove if you have the correct TE/AMP pin remover.
However, I consider DSub pin removers to be disposable items — it’s hard to use them more than a few times.Â Sometimes they work great, often they’re a challenge.Â Micro-Fit and Mini-Fit pin removers are similar, and if the wire breaks, it’s even harder.Â Plus the Micro-Fit/Mini-Fit pin removers are only slightly more robust than DSubs, but a lot more expensive (>$15 versus ~$5).
First off, my apologies for not posting at all for a couple months.Â I have been very busy with a combination of work (new project with a tight schedule), family activities, taxes, and such.
I will not make any specific promises, but my life has calmed down a bit, and I will do my best to get more posts out – I have way too many partially written posts.