Section 3.2 - Operational Analysis; Utility Voltage Present; Transfer To Standby; Transfer To Utility - Generac Power Systems CorePower Repair Manual

TRANSFER SWITCH

UTILITY VOLTAGE PRESENT

When Utility voltage is present, the circuit may be briefly
described as:
• Battery voltage is available to B+ (194 or 15B) and B- (Wire
0) from the generator.
• The internal K1 relay is de-energized.
• K1 contacts 11 and 13 are in their normally closed state.
• K1 contacts 8 and 7 are in their normally open state.

TRANSFER TO STANDBY

With the Generator running during a Utility failure, the circuit
may be described as:
• Battery voltage is available to B+ and B- from the generator.
• A ground has been applied to Terminal XFER (Wire 23) via
the generator controller.
M
M = SERVO MOTOR
K1 = TRANSFER RELAY
LS1 = LIMIT SWITCH
LS2 = LIMIT SWITCH
PART 3
BLACK
RED
LS2
Figure 29. EZ Operator Electrical Schematic
• The K1 relay is energized, contacts 11 and 13 open, and
8 and 7 close completing a path for current to flow to the
servo motor.
• The servo motor will operate till LS2 is mechanically
opened, interrupting the current flow to the servo motor.

TRANSFER TO UTILITY

With the Generator running and Utility restored, the circuit
maybe described as:
• Battery voltage is available to B+ and B- from the generator.
• The return to utility timer has expired and the ground has
been removed from the XFER terminal (Wire 23).
• The K1 relay will de-energize, contacts 11 and 13 will close,
and 8 and 7 will open completing a path for current to flow
to the servo motor.
• The servo motor will operate till LS1 is mechanically opened
and LS2 will mechanically close.
B
K1
A
K1
9 10
11 13
2
LS1
1
3
2
1
3
K1
8 7
6 4
Section 3.2
Operational Analysis
B -
XFER -
B +
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