What is the difference between locking molex and PWM connectors other then the locking feature?

Technical Electrical
#1
  1. Are the crimp terminals of PWM and Molex connectors the same piece?
  2. Are the crimp tools for PWM and Molex the same? We already own a PWM tool similar or the same as the andymark one.
  3. Spectrum’s Mentor mentioned they switched this year to PWM connectors with zip ties because they had trouble with crimping. Is there any more information about this issue because we like the latching feature built into the Molex connectors.

Clarification
where I mention PWM connectors I am talking about the connector type that andymark sells. I don’t remember where we got ours. I was not the one worring about canbus connectors when we bought that 4 years ago. We soldered it last year due to problems with PWM which researching now I have found they were crimping wrong. Soldering is reliable but terrible to work on.
Crimp Tool: PWM crimp tool multi-series contacts - AndyMark Inc
Male Connectors: PWM Male Connector 25 Housings 100 Pins - AndyMark Inc
Female Connectors: PWM Female Connector (25 Housings, 100 Pins) - AndyMark Inc

#2

It is possible to crimp the locking connectors and never have a failure. We weren’t able to do it and we didn’t see a benefit in cutting off the non-latching connectors that come pre-installed on the Falcons and Spark Max cables with factory made crimps to install our own that increased the failure rate and cost. Since the standard CAN cables don’t include a center wire it’s very easy to insert a small (4") zip-tie on them to ensure they don’t come undone.

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#3

You’re going to have to be more specific. PWM is a type of modulation, and Molex makes thousands of different families of connectors.

#4

There are also a number of Cable Clips the are available from different vendors. One is included with every SPARK MAX to help with retention if you don’t want to use a zip tie.

Personally I have done both.

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#5

I have not used that specific crimper, it looks like a generic one for dupont crimps. If you do decide to use the Molex SL series connectors, I would recommend this crimper. In my opinion, while it is slower to use a non-ratcheting crimper, it is a lot easier to use and control.

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#6

There’s a lot of info here in other threads – for example, Split Topic: Crimping 0.1" Molex connectors for PWM/CAN cables - Electrical - Chief Delphi. There are a great many connectors, cables, etc. For some, the best option is buying pre-made cables, and “PWM” is sometimes used to describe these. For others, making custom cables works well.

If you make your own, there are several types of pins, housings, crimpers, etc. As with many things, there are more ways to get this wrong than right, so leave time for practice/reordering and/or have pre-made cables as a backup. The AndyMark page doesn’t seem to give the manufacturer part numbers, so it’s hard to say. These probably do match a Molex part, but it’s impossible to be sure, without more info.

If you had trouble with the AndyMark parts in the past, you may want to favor per-made cables.

#7

“PWM” connectors that andymark sell are what are colloquially called “dupont” connectors. Still not a helpful name, so here is a helpful post on finding the correct parts for that system. This source says a good brand for these is the Harwin m20 line

Not sure what the Molex parts you are describing are, if it’s the SL series, no they aren’t interchangeable – the retention mechanism is part of the contacts not the housing

Addressing OP’s questions:
1- no
2- yes* (you can get good-enough results with the PWM but may have trouble getting it into the housing, but it works much better on the molex SL series apparently, see links above)
3- imo the rev or vexpro cable clips aren’t worth the plastic they’re made of. they fall off easily, and hardly inspire confidence in the connection. Using a zip tie across the connection gives me 100% certainty that it isn’t coming apart accidentally. Just sneak a small one, the 4 inch long, 1/8 or so wide type, between the wires on each side.

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#8

After reading spectrum’s guide, we switched to SL locking clips for 1 year. We loved them, but they are not directly compatible with the interfaces on the rev controllers. Molex makes SL non-locking connectors which we prefer. We use zip ties and the retainers. I wish there were some nice small reusable zip ties. That would be helpful. Also, I wish Molex made single pin SL housings. There are many times when we need those, and they are the only reason we keep Duponts around.

#9

If building your own using Molex SL, it’s worth trying out the “high force” pins (on the socket side): 71851. The advantage here is these stay on pretty well, no matter what they are connected to. Of course, if they are plugged/unplugged many times, bent, etc. this won’t apply. It makes a huge difference having the right crimper, and getting good wire also is pretty helpful.

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#10

I have used heat-shrink to “lock” PWM connectors. A piece of tubing 1-1/2" to 2" (e.g. 40mm) long and 8 to 10 mm in diameter will shrink in to a nice keeper for 3-pin dupont (PWM) connectors. As long as you don’t use marine tubing (which has a mastic goop), it’s also easy to remove if you need to swap connections, with a sleeker profile than thin cable ties.