9-20 MM2 Motor Manager 2
GE Power Management
9.7 AUTOTRANSFORMER OPEN TRANSITION STARTER 9 STARTER TYPES
9
9.7 AUTOTRANSFORMER OPEN TRANSITION STARTER 9.7.1 DESCRIPTION
This starter type is a reduced voltage starter. When the start button is pressed, timing relay TR is
picked up and seals itself in. The 1S coil is also picked up which then picks up the 2S coil. The 1S
contacts configure the autotransformer windings into an open delta for two winding or wye for three
winding autotransformers. The 2S contacts bring the autotransformer on line providing reduced volt-
age to the motor. When the timing relay TR times out 1S and 2S drop out and then contactor coil R
picks up and full voltage is applied to the motor.
Figure 9–15: ELEMENTARY AUTOTRANSFORMER OPEN TRANSITION STARTER
To program the MM2 for autotransformer open transition starter, set:
S1 CONFIGURATION\STARTER\STARTER TYPE: AUTOTRANS OPN TRANS
S1 CONFIGURATION\STARTER\CHANGE OVER TIME: 1 to 125 sec.
S1 CONFIGURATION\STARTER\CONTACTOR SEQUENCE: 1S-2S, 2S-1S
S1 CONFIGURATION\STARTER\STARTS PER HOUR: 1 to 40