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a. The load connection group consists of the voltage reconnection board, the main load contactor, the load terminal board, and the current transformers.
b. The voltage reconnection board consists of a stationary terminal board and a movable link-type board. It provides a means of connecting the two coils of each phase of the generator assembly to provide all specified output voltages. Simultaneously, it reconnects all other circuits necessary to convert the generator set from 120/208 to 240/416 Vac operation.
c. The voltage reconnection board is connected to the load terminal board through a three-pole three-phase main load contactor. This contactor is controlled by the circuit breaker switch of the control cubicle assembly. The main load contacts will automatically open when any of the protective devices actuate or when the START-RUN-STOP switch is placed in the STOP position.
d. One lead of each of the two coils of each generator phase is connected directly to the voltage reconnection board. The remaining two leads of each
phase pass through a three-window current transformer. The proportional current Induced in the transformer is used by the static exciter and voltage regulator assembly as a current boost. The leads then pass through a second three-window transformer. The proportional current induced in this transformer is used in the load measuring unit and the ammeter and watt-meter circuit of the control cubicle. The leads of two of the generator phases then pass through a single-window crosscurrent transformer. The current induced in the crosscurrent transformer is used for reactive power compensation during parallel operation. Local voltage sensing and adjustment are accomplished across a single coil of the remaining phase.
5-5. VOLTAGE RECONNECTION BOARD ASSEMBLY. ,
Refer to the Operator and Organizational Maintenance Manual for voltage reconnection board assembly removal, maintenance, and Installation procedures.
5-6. MAIN LOAD CONTACTOR.
(1) Remove screws (1, figure 5-2), lockwashers (2), and flat washers (3) to remove terminal covers (4).