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Wiring Diagrams-single phase reversible motors
2

Wiring Diagrams-single phase reversible motors

Wiring Diagrams-single phase reversible motors

(OP)
I have a 3/4 h.p. reversible single phase motor for a small lathe. The motor is of the capacitor start, induction run type, with seven wires. The wires are marked; T2 T3 T4 T5 T8 P1 P2.  From my control switch, I have four wires exiting to the motor. These are as follows;

switch in REV:                        switch in FWD
   blue:  HOT                            blue:  HOT
   yellow: HOT                           yellow: neutral
   black: neutral                        black: HOT
   red: neutral                          red: neutral

My question is; how do I connect all these wires together to accomplish being able to operate this motor in forward or reverse with the switch? Any help/suggestions would be very much appreciated.  Craniac.
                                                                             

RE: Wiring Diagrams-single phase reversible motors

Suggestion: Start with the motor schematics. Then, align wire colors properly. Generally or theoretically, the forward / reverse switch will just swap coil conductors in the motor winding connections.

RE: Wiring Diagrams-single phase reversible motors

To reverse direction of a 1ph motor the start winding circuit must be reversed in relation to the run winding circuit. Identify the run and start circuits of your motor. The run will go across the blue and red and the start across the yellow and black at the switch. This would appear to reverse the start circuit from the information you give.

RE: Wiring Diagrams-single phase reversible motors

You have a dual voltage (115/230v) split-phase motor with a thermal protector -- it does not have capacitor start.  P1 and P2 are the terminals for the thermal protector.

for 115v CW rotation of the motor, make the following connections:

a) connect P1 to the blue wire on switch.
b) connect T2 and T4 to the red wire on switch.
c) connect T5 to the yellow wire on switch.
d) connect T8 to the black wire on switch.
e) connect P2 and T3 together.
reverse T5 and T8 if this rotates the wrong way for "forward"

for 230v CW rotation, make the following connections

a) connect P1 to the blue wire.
b) connect T4 to the red wire.
c) connect T5 to the yellow wire.
d) connect T8 to the black wire.
e) connect T2 and T3 together.
f) do not connect P2, it is connected internally.
reverse T5 and T8 if this rotates the wrong way for "forward"

hope this helps out...

RE: Wiring Diagrams-single phase reversible motors

Sorry, the starting coil could have a capacitor in series with it... either way, the connections should be the same -- P5 and P8 are the connections for the starting coil.

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