Home Forums General Discussion Technical Questions MCE AC-Drive controller issue

MCE reports that some of their AC-Drive controllers will need to have a monitoring circuit installed in them. This circuit is designed to detect a shorted transistor which will then cut off the power to the circuit, which will limit the loss to just the drive. Failure to protect this scenario means power would continuously flow into the braking resistors and, over time, can cause heat and fire that will damage the resistors, surrounding components, and controller. We have been told that we do not have to do this @$3500 but it is highly recommended. Any experience on this issue and why MCE feels that we should have to pay to correct what seems to be a design flaw?

I just installed 3 of these MCE mod kits. It's kind of like paying for home insurance with a paid off mortgage. You don't have to pay it but it is highly recommended. More than likely your house won't catch on fire and burn to the ground but if it does, well...

Is it all of their AC-Drives? We have quite a few of these, and have not been notified. I will reach out to them today to get the details.

Hey solidstate FYI https://www.technicalsafetybc.ca/re...-icontrol-and-motion-4000-drive-failures

I haven’t heard that we’re supposed to be going back and adding this to all IMC-AC controllers but I have done a few of these wiring change kits on IMC-AC, VFMC, & a Motion 4000 controller. They’re sending the kit when we replace an F5 drive. For a few years now the new F5 drives have been coming with a set of Amp Traps and just this year these kits are in the box. I’ve assumed it’s because of the high failure rate of the F5 drives and we wouldn’t get warranty support if it isn’t done. I’ll check out that bulletin though.

Thermal protection is required.
Here is KEBs video put out around the time MCE came out with the thermal kit fix. All braking resistors should have some sort of thermal protection.
https://m.youtube.com/watch?v=PmWIEzqlvI0

Interesting video; what I don't understand is why proper thermal protection was not designed in to the controller originally and why we have to pay MCE a whole bunch of money to fit a design flaw that MCE of KEF should have corrected a long time ago. Is anyone aware of any lawsuits regarding this issue and their outcomes?