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reversing motor wiring

reversing motor wiring

(OP)
I'm getting no help from the motor mfr...and have not seen this before, so forgive me
if it's common, but I have a customer who has wired a singlephase motor as shown in this diagram using reversing contactors, and has told me that "it works". I'll have to attach the motor wiring from the data sheet separately apparently.

RE: reversing motor wiring

Fairly common scheme.

http://1.bp.blogspot.com/-GPLuyJVOJ8A/UutKRqiezbI/... which was lifted from http://ijyam.blogspot.co.uk/2014/01/electrical-con...

The way it is drawn makes it look look like a 3-phase Y-connected motor, but the 'star point' is actually the centre-tap of the two main windings in series.

T8 is connected to the centre-tap, therefore connecting T5 to L2 instead of L1 reverses current flow through the starting winding, thus reversing the direction of rotation. It's an elegant scheme, but not drawn in a particularly intuitive format.

RE: reversing motor wiring

he motor has three 115 Volt windings. Two run windings and one start winding.
The run windings are in series across 230 or 240 Volts. The start winding is across one or the other of the run windings and picks off near 115 Volts or 120 Volts.
The start winding is reversed in relation to the run windings to reverse the motor.
In this case the rvesal of the start winding is accomplished by connecting one end to the center tap of the two run windings in series and connecting the other end to either L1 or L2.
This works fine.
There are other connections to accomplish the same reversal.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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