Generator AC Lead Connections

Standby Generator Sets

General Information

See “Voltage Codes”. This generator may be rated at any one of three voltages, either single-phase or three-phase. The electrical wires in the unit’s AC con- nection (lower) panel should be installed according to the number of leads and the voltage/phase required for the application. If there are any questions regard- ing lead connection, refer to the wiring diagrams at the back of this manual.

Voltage codes apply to the type of stator assembly installed on a particular generator.

FOUR-LEAD, SINGLE-PHASE STATOR

Four-lead generators (see Figure 7.1) are designed to supply electrical loads with voltage code “A” (240V, 1-phase, 60 Hz). Electrical power is produced in the stator power windings. These windings were con- nected at the factory to the main circuit breaker as shown in Figure 7.1.

The rated voltage between each circuit breaker ter- minal is 240V. The rated voltage between each circuit breaker terminal and the neutral point 00 is 120V.

Figure 7.1 — Four-lead, Single-phase Stator

ALTERNATOR POWER WINDING CONNECTIONS

3-PHASE ALTERNATORS

The generator is designed to supply 3-phase electri- cal loads. Electric power is produced in the alterna- tor power windings. These windings were connected at the factory to the main circuit breaker with a “Y” configuration as shown in Figures 7.2 and 7.3.

The rated voltage between circuit breaker terminals E1-E2, E1-E3 and E2-E3 is either 480V or 208V depending on the model.

The rated voltage between each circuit breaker termi- nal and the neutral point 00 is either 277V or 120V depending on the model.

Figure 7.2 — Stator Power Winding

Connections - 3-phase, 277/480V (6 Lead)

S1	E1
INTERNAL
CONNECTIONS
			L-L
S6	S4
		NEUTRAL
		NEUTRAL
	S5
E3 S3		S2	E2
		S2	E2

L-N

Figure 7.3 — Stator Power Winding

Connections - 3-phase, 120/208V (6 Lead)

S1 S1

	S4		S4		L-L
				00 (NEUTRAL)
	S6		S5

S3	S6	S5		S2

E3	S3			E2
				S2

L-N

7-1

08/05

0 .Rev ACConn001