How to test motor phase wires?

[electr0n]

I recently blew out my controller trying to run my HS3540 motor with my old Crystaltye controller. My controller is toast. There are at least two blown mosfets and 1 capacitor blew up and I'm not reading any resistance on a bunch of tiny resistors on the board. I'm not sure what caused the failure although I suspect I probably drew too much current. I had modded the 20 amp controller by adding some solder to the shunt a few days earlier. It was running fine on my 407 motor so I hooked it up to my HS and it blew up in about 5 minutes of testing full throttle and acceleration etc.

So now I'm wondering if the failure was caused by the wire cut issue that is common on the HS3540 motors. Although I did install a little metal sleeve to protect the wires I can't see under the seal to be sure the wires are ok. Is there some way I can test the phase and hall wires without opening up the motor and using a multimeter? I don't have a testing tool.

I've got some replacement controllers on the way but I'm worried if the wires in my HS3540 are shorted together or something that I may damage the new controllers so I'd like to confirm everything is ok prior to plugging in the next controller. Are there some simple tests I can do to try to verify the wiring in the motor is ok?

 

[MadRhino]

Just test the current on phase wires while spinning the motor, it will generate current to each phase alternatively.

 

[dnmun]

check continuity to the hub for each phase wire. if it shorted to the hub you will see a low resistance because of the short to the hub, and for the phase wires to each other, the resistance will be low for each of them to each other but not to the hub, and if one broke or separated, it will be open. shorted to the hub is bad.

most likely just too much current for the mosfets after you modded the shunt.

 

[electr0n]

When you say check for continuity between the phase wires and the hub does that mean one probe on the hub casing and the other on each phase wire?

Testing for phase wires shorted together I would connect 1 probe to a phase wire and the other probe to the other phase wires and resistance should be high correct if they are not shorted together? How will I know if one of the phase wires are open?

To test the current on the phase wires I'd connect each probe to a phase wire and spin the wheel and should get some amperage flowing between the phases?

What about the hall wires any way to verify they are intact with a multimeter and a dead controller?

 

[dogman dan]

Or the John in CR method.

Seperate the phase wires at the plug end so none touch. Unplugged from the controller. Spin the wheel. Easy? you have no shorts. Touch two wires together, and it should resist a lot, and resist more if you touch all three wires.

 

[electr0n]

Very easy. Thanks Dogman. When the motor is disconnected from the controller it is easy to spin. Will try jumping a couple phase wires together to feel what the resistance is like that way.

Now how about the hall wires, any simple way to verify they are intact with a multimeter or some other simple way?

 

[dnmun]

nope, need the controller working or the lyens tester

the phase wires are all connected so they will appear shorted to each other, but they should not be shorted to the hub.

if they are, then something happened to cause them to short, but you still need the controller or lyens tester to see if the halls also shorted.

 

[dolby]

Or the John in CR method.

Seperate the phase wires at the plug end so none touch. Unplugged from the controller. Spin the wheel. Easy? you have no shorts. Touch two wires together, and it should resist a lot, and resist more if you touch all three wires.

I have used this test since I am having some intermittent problems with my motor starting. Using this test I find that only 2 of the wires touching (yellow and green) will cause resistance on the wheel spinning. The third blue phase wire does not cause any resistance when touching either the yellow or green phase wire. Does this mean that I have a break in the blue wire, possibly in the motor?

 

[dogman dan]

Yep. Your failure to start is happening when you are aligned on that phase. Open it up, you might just have the wire unsoldered from the stator wires. Or a cut wire at the axle.

Look at all the wire too, I failed to see where a tire rubbed a wire for a long time once. It was so obvious when I finally saw it, but I was all focused on the plug.