Utility Source Voltage Failure - Guardian 4389 Repair Manual

"V-TYPE" PREPACKAGED
TRANSFER SWITCHES
If utility source voltage should drop below a preset value, the generator circuit board will sense the dropout. That
circuit board will then initiate generator cranking and startup after a time delay circuit times out.
Figure 4 is a schematic representation of the transfer switch with generator power available, waiting to transfer.
• Generator voltage available E1, E2.
• Circuit board action holding Wire 23 open to ground.
• Power available to standby coil C2, upon closure of TR, normally open contacts (9 & 6) will close and initiate a
transfer.
E1
N1A
E1
N1A
126
N1A
B
126
NO O NC
XA
COM
B
VR1
N2A
A C1
ATS
N2A
B
LEGEND
ATS-AUTOMATIC TRANSFER SWITCH
C1-UTILITY COIL & RECTIFIER
C2-GENERATOR COIL & RECTIFIER
F1,F2-5A, 600V FUSE
LC-CIRCUIT BREAKER (LOADS)
TR-TRANSFER RELAY
TS-TERMINAL STRIP
XA,XB-LIMIT SWITCHES
PART 3

UTILITY SOURCE VOLTAGE FAILURE

194
194
A
23
9 9
TR
6
B
23
205
N2A
N1A
N1A
E1
N2A
205
B
N1A
N2A
E1
NC C NO
E2
COM
VR2
C2
T1 T2
T1
B E2
T2
E2
UTILITY
DC
GROUND
GENERATOR
Figure 4. Generator Power Available, Waiting to Transfer.
194
23
OPEN
F2
N2
F1
N1
E1
E2
E1
E2
NEUTRAL
CONNECTION
INSIDE SWITCH
E2
BLU
VIO
YLW
BRN
BRN/WHT
YLW/WHT
GRY
PNK
LC
SECTION 3.2
OPERATIONAL ANALYSIS
194
12Vdc TRANSER
COIL
23
TS TO
GENERATOR
CONTROL PANEL
N2
240VAC
OUTPUT
N1
BLACK
TO GENERATOR
RED
OUTPUT
CIRCUIT BREAKER
NEUTRAL (WHITE)
NEUTRAL (WHITE)
240VAC TO
RED (MAIN 2) MAIN DISTRIBUTION
PANEL
BLACK (MAIN 1)
15A/120V CIRCUIT 6
15A/120V CIRCUIT 5
20A/120V CIRCUIT 2
30A/240V CIRCUIT 1
CUSTOMER
CIRCUIT
CONNECTION
30A/240V CIRCUIT 3
15A/120V CIRCUIT 4
15A/120V CIRCUIT 7
15A/120V CIRCUIT 8
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