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Bad crimping in Dostar J1772 handles sold long ago from OpenEVSE

In the vein of another discussion, which was regarding temperature monitoring of the J1772 handles, I was experiencing some really warm handles, or at least, I noticed them. I've had my Dostar 32 amp cable and plug combo that I purchased from maybe 5+ years ago.  It was getting warm enough that I was concerned, so I opened the handle and started checking the connections with a gentle tug. While I was doing this, the big white wire pulled right out of the connector!!  So there was the problem. I further disassembled the handle and connector and discovered that it was just that one power pin that wasn't crimped well. It WAS crimped, but not tightly enough. The crimp looks like it was put in with one of those hexagonal die hydraulic crimpers, so probably the right equipment anyways. And the wire itself didn't look bad at all, no discoloration from heat and no signs of water ingress or corrosion, it just didn't seem crimped all the way down, and was getting hot. I'd estimate upwards of 140 degrees. Not hard to see how a poor connection could account for this much heat. In fact, I was able to force the wire right back in to the pin. So that's what I did, and soldered the damn thing. It no longer gets warm. I run at the full 32 amps in to a Bolt EV. I'd have hated to see what the eventual outcome of this would be had I not intervened. 

So, anybody with older Dostar handles, do a quick check for your own good. Or any handle for that matter. 

Great job recognizing and correcting the issue. You are correct your cable was purchased in January 2015, about 5 and a half years ago. The cable you purchased was a Dostar 32A cable built in the Dostar factory. Since 2015 Dostar has significantly improved their product. The product sold by OpenEVSE today is the Dostar v3 handle which is UL certified to 50A and assembled in North Carolina by OpenEVSE. We use premium tinned cable (reduces the possibility of oxidation/corrosion) made custom for OpenEVSE in California with 2 - 12AWG conductors, which can pass more current is lighter and more flexible.

Your advice is sound, it really does not matter which cable you have or how old it is... Charging stations pass a huge amount of power, keep an eye on your equipment.

Inspect your plug's listen to this advised

it happen to me 



Andrew, I love soldered connections for low-current and low-voltage applictions, but they're really not appropriate for high-current devices, where mechanical crimping is the standard, and not for cost reasons.

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Thanks Al, This is an area that I'm familiar enough with too. I really wish I could have found some replacement pins to reinstall. I have a hydraulic crimper and everything, but I just can't seem to find new pins. Soldering was the next best thing I had, and at least we can say there isn't much flex in that area, and I was able to sufficiently heat the pin and wire to get it to wet out properly. It's only 10 AWG after all. That being said, if I could get my hands on a set of pins tomorrow I'd take the whole thing apart and put brand new ends on every wire without a second thought. Thanks for your concern. If it gets whacky again. I have a shorter cable off an old Blink charger I could use, but I'd have to dial it back to 24A. Maybe it's high time I got a fatter cable anyways.

on my research I found EV West has Pins for 32A unit  but I also  saw how expensive the crimper cost "for one time use"  so just order whole new cable with plug . and unit is back online happy to report..

assembly guide mentions Crimp Ground pin with Pico Corporation 400B pneumatic crimping tool at 80PSI 

Required Die Pico 414DA-8N and Required Die Pico 414DA-12N

that thousands $$$

wonder if 10 Ton Hydraulic Wire Battery Cable Lug Terminal Crimper Crimping Tool 8 Dies Fit for Crimping wires under $40 could do job.

I have a second unit I bought on ebay with homemade J1772 cable  that going to use my old cable on with new J1772 plug/handle

The J1772 pins are readily available (though not particularly inexpensive at the first two sources I found):

OpenEVSE has a guide on crimping the connectors:

. . . and, apparently, used to sell them too, according to that guide:

"This guide provides the assembly procedure for SAE J1772 cable from parts available from at OpenEVSE . . . 

Crimp Power pins with Pico Corporation 400B pneumatic crimping tool at 80PSI.  Required Die Pico 414DA-8N"

I've been trying to track down the spec on those pins and sockets, but it's an internet rabbit hole and I'm supposed to be working.  Point is, they can be had.  

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