Looking for projects ideas or hacks for ecm motors
 

I've have received 2 motors that no longer work but I believe have some use or potential. I haven't opened them up yet but its usually a bad control module which can be removed leaving a dc motor/generator. The true ecm is rated for 1/2 to 1 hp. The second is a x-13 constant torque motor and is smaller 1/8 to 1/3 hp. Wind generator or something else? Its not terribly windy here. If I get the x13 working again I could replace my psc blower motor in my furnace for potential savings. That's often the difference between 14 SEER and 15-16 SEER equipment.

Connect it to a stationary bicycle to make a bicycle generator.

There are videos on Youtube where some of those have a defect where a single component blows and the unit gets warrantied. I think it was the MOV that goes open circuit but it might be something else. Since it is designed to protect the motor and the motor failed, some people just put in a jumper. Not sure if it acts as a supplementary protector or not, so if it was me, I'd play it safe and replace the ~$5 part if that was what failed.

unlike UL, CSA stipulates that any AC motors must come with additional form of protection from overheating (which the winding insulation may break down causing shorts--- fire). An additional thermal fuse must be included into all AC motors, so that when the coil overheats, it would burn out the thermal fuse to protect from burning.

If your motors are CSA rated, maybe there's the additional thermal fuse within that is burned open circuit. Check to see if that's the case.

Lastly: that's a thermal fuse, not an MOV, for MOV doesn't open circuit to protect the device from overheating...MOV only absorbs power surge (spikes) and dissipates it into form of heat.

More on the subject of MOV if interested.

Quest

It's a thermistor that I was talking about, not a MOV, and not a thermal fuse. I'm aware AC motors should have thermal fuses, I've pulled apart a few and have seen them although not all are the 'blow the fuse and replace the motor' type, some reset once they've cooled off.

https://www.youtube.com/watch?v=Z4642CZHtaE

Those eco motors have a quite high failure rate and are very expensive. My friend had his quit last year and it was a $500 motor from the supply house. A few $ more and you can just replace the whole air handler. They do make for a more efficient unit but when the motor dies and it's a $500 motor all of that energy savings is gone. That's why ac guys that know the systems don't recommend anything over 16 seer. Parts price and high failure rates outweigh any energy savings.

The ones I have looked at usually had blown capacitors which is an easy fix. Use good high temp rated ones not the cheap brand caps many manufacturers use.

I'll open mine up this weekend if I get the time. Both were doa. With ECM you can usually replace the module end with all the caps, still $250 for the module.

Let us know what you find.

There isn't a whole lot to those ecm controls as far ad parts go. A chip senses current and voltage at various places and commands a few power transistors.
http://www.anaheimautomation.com/man...DC%20Motor.png
The stickler is how the elements are housed: some manufacturers take the extra step of encapsulating the control in epoxy. These modules are impossible to service at the component level.

The video mn renovator posted was all about the ptc thermistor. It looks like this is the mandatory current limiting device described. The failed one in the video can likely be repaired by soldering the leg back onto the body with silver solder. Old school crt displays had one of these wired in series with the degaussing coil to demag the screen on power up. I have no idea how many of those things I fixed, but it was a lot.

I bought a repair kit for $20, comes with a mov and a wooden peg. I haven't moved on it mostly because the smaller motor in the more useful size for me is 240v and my gas heaters have 120v blowers. Hoping either a small ecm 120v blower or condenser fan might come my way before summers over. My 15 seer has both, my 14 seer has neither but will probably outlast the former.