“V-TYPE” PREPACKAGED
TRANSFER SWITCHES
SECTION 3.1
DESCRIPTION & COMPONENTS
PART 3
Page 41
TRANSFER MECHANISM
The 2-pole transfer mechanism consists of a pair of
moveable LOAD contacts, a pair of stationary UTILI-
TY contacts, and a pair of stationary STANDBY con-
tacts. The LOAD contacts can be connected to the
UTILITY contacts by a utility closing coil; or to the
STANDBY contacts by a standby closing coil. In addi-
tion, the LOAD contacts can be actuated to either the
UTILITY or STANDBY side by means of a manual
transfer handle. See Figures 2 and 3.
UTILITY CLOSING COIL C1:
See Figure 4. This coil is energized by rectified utility
source power, to actuate the load contacts to the
“Utility” power source side. When energized, the coil
will move the main contacts to an “overcenter” posi-
tion. A limit switch will then be actuated to open the
circuit and spring force will complete the retransfer to
“Standby”. A bridge rectifier, which changes the utility
source alternating current (AC) to direct current (DC),
is sealed in the coil wrappings. If coil or bridge rectifi-
er replacement becomes necessary, the entire coil
and bridge assembly should be replaced.
STANDBY CLOSING COIL C2:
Coil C2 is energized by rectified standby source
power, to actuate the load contacts to their “Standby”
source side. Energizing the coil moves the load con-
tacts to an overcenter position; limit switch action
then opens the circuit and spring force will complete
the transfer action to “Standby”. This coil’s bridge rec-
tifier is also sealed in the coil wrappings. Replace the
coil and bridge rectifier as a unit.
LIMIT SWITCHES XA1 AND XB1:
Switches are mechanically actuated by load contacts
movement. When the load contacts are connected to
the utility contacts, limit switch XA1 opens the utility
circuit to utility closing coil C1 and limit switch XB1
closes the standby circuit to standby closing coil C2.
The limit switches “arm” the system for retransfer
back to “Utility” when the load contacts are connected
to the “Standby” side. Conversely, when the load con-
tacts are connected to the “Utility” side, the switches
“arm” the system for transfer to “Standby”. An open
condition in limit switch XA1 will prevent retransfer to
“Utility”. An open switch XB1 will prevent transfer to
“Standby”.
Figure 2. Load Connected to Utility Power Source
Figure 3. Load Connected to Standby Power Source
Figure 4. The “V-Type” Transfer Mechanism
UTILITY
CLOSING
COIL (C1)
STANDBY
CLOSING
COIL (C2)
BRIDGE
RECTIFIER
BRIDGE
RECTIFIER
MANUAL
TRANSFER
LEVER
LIMIT
SWITCH
(XA1)
N1
N2
E2
E1
T1
LIMIT
SWITCH
(XB1)
T2
N2A
A
B
E2
STANDBY
LOAD
UTILITY
STANDBY
LOAD
UTILITY
Содержание 4721
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Страница 109: ...ELECTRICAL DATA V TYPE TRANSFER SWITCH 100 200 AMP 2 POLE PART 9 Page 105 DRAWING 0F0015 A 2 of 2...
Страница 112: ...PART 9 Page 108 ELECTRICAL DATA WIRING DIAGRAM 1 5 LITER LIQUID COOLED ENGINE DRAWING 0E0343 B...
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