GE MM3, Instruction Manual, Page: 28 / 230

2–10 MM3 MOTOR MANAGER 3 – INSTRUCTION MANUAL
STARTER TYPES CHAPTER 2: INSTALLATION
Reverse (if the motor is running in the forward direction) sequence:
1. Start B command is received by the MM3 Motor Manager 3 (serial, switch input
or faceplate).
2. Open Contactor A relay – the motor is now off line
3. Wait the required transfer time.
4. Close and maintain Contactor B output relay – the motor is now across the
line in the reverse direction.
All output relays de-energize when the MM3 Motor Manager 3 power is interrupted,
causing them to open and stop the motor. The MM3 Motor Manager 3 can only be wired for
fail-safe operation.
If used, the VT input must have a separate PT so that the current and voltage inputs remain
in phase regardless of which direction the motor is running. See the following figure.
If feedback is not received from either the F or the R contactor to Contactor Status N.O.
inputs within one second of closing Contactor A or B output relays, an OPEN CONTROL
CIRCUIT alarm will occur. This will cause the currently closed relay to open.
If feedback remains at the Contactor (A or B) Status N.O. input more than one second after
opening Contactor A or B output relays, a WELDED CONTACTOR alarm will occur.
Figure 2-7: Full-voltage Reversing Starter
GE POWER MANAGEMENT