Direction of n AC motor

We had to take apart a motor from a Rigid thickness planer to resurface the commutator. We reassembled the motor and as crazy as this sounds we think that its now running in reverse. If we inadvertently reversed the wires to the brushes would this happen? That seems to be the only variable here. Thanks, Lenny

You have hit it in one :-)

if the motor has 4 wires then yes, you could of reversed the stator wires.

In cases where there are only two wires and you disconnected the wires from the stator, you may not have used the correct wire in the stator.

This assumes you are talking about a series type motor.

But pulling a basic series motor appart for a basic clean up should not cause pain.

I suppose if you damaged one of the wires in the rotor by shorting together It could go the otherway, however, it should also not spin as fast as it should have less power now at the shaft and same current or more.

Jamie

If I recall correctly a series wound AC motor will not reverse by just changing the wires to the brushes. You would need to reverse the connections to the field winding. One end of the field winding is connected to one AC line and the other end to a brush. Then the current flows through the rotor windings and out to the other brush and from there to the other AC line. Did you maybe swap the field winding connections? Eric

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he commutator. We reassembled the motor and as crazy as this sounds we thin k that its now running in reverse. If we inadvertently reversed the wires t o the brushes would this happen? That seems to be the only variable here. T hanks, Lenny

I'm pretty sure that a typical washing machine motor for instance does not have brushes. I think that would make it an induction motor. I have some sp are Maytag washing machine motors down in the basement that I liberated fro m machines at the town dump. They run at 1725RPM, (I think that speed is di rectly related to line frequency), and I don't think they have brushes eith er. They do however have centrifugal switches though. So I think that would that make that type of motor a compound type.

My tool motor has two wires coming out of the field that go directly to the AC line. On the other side of the field there are two more wires that go t o the brushes. There is no centrifugal switch. And that's it, a very simple scenario. This one I think is a series motor. The other thing is that this Rigid motor spins at 9000 RPM. We're going to try to reverse the brush w ires and see what happens. Thanks everyone for the replies. I'll let you k now how it turns out. Lenny