Description - GE MM3 Instruction Manual

9 STARTER TYPES
9.8 AUTOTRANSFORMER CLOSED TRANSITION STARTER
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 in turn picks up the 2S coil. The 2S coil seals itself in.
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 voltage to the
motor. When timing relay TR times out the 1S coil drops out and then R is picked up. When the R contacts pick
up then 2S is dropped out. The motor now has full voltage applied.
Figure 9–18: ELEMENTARY AUTOTRANSFORMER CLOSED TRANSITION MAGNETIC STARTER
To program the MM3 for autotransformer closed transition starter, set:
S1 CONFIGURATION\STARTER\STARTER TYPE: AUTOTRANS CLS 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
S3 PROCESS\PROGRAMMABLE INPUTS\INTERLOCK INPUT 10: AUTOTRANS 2S CONTACT
S4 CONTROL\AUX RELAY 1 CONFIG\AUX RELAY 1 FUNCTION: AUTOTRANSFORMER 2S
The CONTACTOR SEQUENCE setpoint appears when the Autotransformer Closed Transition starter type has been
selected. The 1S-2S value means that the 1S contactor will close ahead of the 2S contactor as per some man-
ufacturers wiring practices. The 2S-1S value means that the 2S contactor will close ahead of the 1S contactor
as this is another common wiring practice.
GE Power Management
9.8 AUTOTRANSFORMER CLOSED TRANSITION STARTER
MM3 Motor Manager 3

9.8.1 DESCRIPTION

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