Dynamic Mystery

[P.A.Myers]

RedCat rs10 4wd MOA, 390 motors. For changing wheels
I have the car on a wood stand with all 4 wheels
elevated about one inch. When I tighten the nut on
a wheel, sometimes the electric driver I use
will cause the wheel to spin. When that happens the
wheels on the other axle will spin also! The other
axle will spin in the same direction at about the
same speed as the driven axle.

How can that be? The only connections are the motor leads.
These go through the esc that has the battery disconnected.
What is causing the other axle to spin?

[Alexander_0_1]

That's funny! And interesting at the same time. Um, is it because electric motors generate power when you rotate them, and its sending power backwards through your ESC into your other motor on the other axle? I think I've read somewhere that sending power backwards through the FETs on an ESC can damage them ( no idea if its the same for brushed esc ), maybe you shouldn't let your motor,or tires spin while you have your drill hooked up to the tires.

I think it does show you your motors are hooked up in the same direction.

[sdmf]

Bro, your axles and trans are locked. Even on an open diff truck spinning a wheel causes other wheels to spin, if there is no resistance.

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[P.A.Myers]

No trans, the only connections are the motor leads. Whatever is happening has to be electrical, or voodoo.

[sdmf]

Probably induction issue then. Maybe shouldn't be using a drill/driver on an rc either, but that's up to you.

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[P.A.Myers]

Great tool. Excellent torque reaction. Not actually a drill.

[CODYBOY]

Originally Posted by sdmf

Probably induction issue then. Maybe shouldn't be using a drill/driver on an rc either, but that's up to you.

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Please explain, what is a induction issue?

[hotwheels000]

Your motor on the first axle is acting as a generator and sending a small amount of voltage to your other motor.

[sdmf]

Ya the thing is, you likely cannot achieve the same thing with a hand driver. I'm a little out of memory on this, but when you spin one motor with enough rpm, you induce a current. The backfed current is likely jumping the other motor.

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[EeePee]

You can do it with your hand on a stock Clodbuster in 1985.

[binaryterror]

Some of the HV servos when moved fast enough can do the same, provide power back in.

[Eric0424]

Originally Posted by binaryterror

Some of the HV servos when moved fast enough can do the same, provide power back in.

Happens with every servo and at any speed, not just the high voltage and the speed will dictate how much voltage goes back the the receiver. Turned slowly they barely register a volt (.1-.2v), turned enough you can get over 6 volts from one.