The Siren Board

I can see a couple of taper pins in the video. How easy does it spin? With the brushes out it should spin easily and freewheel.

The lack of torque is troubling though. First lets rule out an open field and we can go from there.

If the commutator is dirty enough it can cause poor conduction and lack of torque, but it usually has to be covered in grease or REALLY dirty.

For reference, here is what a motor with an open field runs and sounds like. The commutation on the armature is doing all the work: http://www.youtube.com/watch?v=X9uX9hD5wJY

BTW, dirt is a VERY poor conductor of electricity. It will conduct electricity if the voltage is high enough but it's insulator most of the time.

It spins real nice, especially with the brushes out. I don't feel it scraping or rubbing internally. The commutator is very clean. I noticed today while it was powered, if I lay it on the side it has a very unusual quirk. Usually, Thunderbolt/Model 2s will roll across the floor if put down on their side and powered. Mine does the same, but it rolls, doesn't roll for a brief moment, then will roll again in correspondence to motor RPM (if the motor is at 60 RPM, this will happen 60 times a minute) It is only noticeable at low RPM. At high RPM, it makes it feel like it is off-balance. Throughout testing, though, I noticed that the "no-roll" gap kept getting bigger on powered runs, it seemed. It also gradually ran warmer.

Then I decided to Ohm it out. The 13 amps flowing into the brush holders blew up my multimeter (I remember a loud POP and a pretty orange spark flying into the air, but no scorch marks on the casing... odd), and after that the motor would no longer turn at all under power. I believe I've killed it by accident. I can't afford a Rewind, and I'm sure I can't rewind it myself with the wires that are default. The motor possibly died a noble death that was provoked by an idiot, referred to as me.

In case you were wondering what my multimeter did before exploding, it kept saying 10 to 15, then -1, this happened repeatedly for 2-second intervals.

-1 on my multimeter means it isn't detecting anything.

I said measure ohms, not amps.

holler wrote:I said measure ohms, not amps.

I did. The amps I knew because that was all the wires allowed.

You didn't try to measure ohms when the thing was running, did you?

I took out the brushes and applied power to the thingy, then measured resistance. It gave me feedback. Then it blew up. So, sort of.

sirendude2012 wrote:I took out the brushes and applied power to the thingy, then measured resistance. It gave me feedback. Then it blew up. So, sort of.

UH What!

sirendude2012 wrote:I took out the brushes and applied power to the thingy, then measured resistance. It gave me feedback. Then it blew up. So, sort of.

In my previous post, where did you see the words "apply power to the thingy?"

Apply power to the thingy means, I sent power through the windings, but since the brushes were out, the armature was not powered nor turning but the windings had power.