Generac Power Systems 55, 75, 65 manual Crankcase Breather, 6.– Excitation Circuit Breaker

Models: 65 75 55

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Figure 2-6. – Excitation Circuit Breaker

Section 2

MAJOR GENERATOR COMPONENTS

Rotor will be lost. The unit’s AC output voltage will then drop to a value commensurate with the Rotor's residual magnetism (about 7-12 VAC).

Figure 2-6. – Excitation Circuit Breaker

VOLTAGE REGULATOR:

Six (6) leads are connected to the voltage regulator as follows:

Two (2) SENSING leads deliver ACTUAL AC out- put voltage signals to the regulator. These are Wires No. 11S and 22S.

Two (2) leads (4 and 0K) deliver the regulated direct current to the Rotor, via brushes and slip rings.

Two (2) leads (No. 6 and 2A) deliver Stator excita- tion winding AC output to the regulator.

Figure 2-7. – Voltage Regulator

The regulator mounts a “VOLTAGE ADJUST” poten- tiometer, used for adjustment of the pre-set REFER- ENCE voltage. A lamp (LED) will turn on to indicate that SENSING voltage is available to the regulator and the regulator is turned on.

ADJUSTMENT PROCEDURE:

With the frequency set at 62.5 Hertz and no load on the generator, slowly turn the voltage adjust pot on the voltage regulator until 124 VAC is measured. If voltage is not adjustable, proceed to Section 6 - Troubleshooting; Problem 2.

NOTE: If, for any reason, sensing voltage to the regulator is lost, the regulator will shut down and excitation output to the Rotor will be lost. The AC output voltage will then drop to a value that is commensurate with Rotor residual magnetism (about 7-12 VAC). Without this automatic shut- down feature, loss of sensing (actual) voltage to the regulator would result in a “full field” or “full excitation” condition and an extremely high AC output voltage.

NOTE: Adjustment of the regulator's “VOLTAGE ADJUST” potentiometer must be done only when the unit is running at its correct governed no-load speed. Speed is correct when the unit's no-load AC output frequency is about 62.5 Hertz. At the stated frequency, AC output voltage should be about 124 volts.

CRANKCASE BREATHER

Figure 2-8. – Crankcase Breather

DESCRIPTION:

The crankcase breather is equipped with a reed valve to control and maintain a partial vacuum in the crankcase. The breather is vented to the intake

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Generac Power Systems 55, 75, 65 Crankcase Breather, 6.– Excitation Circuit Breaker, Section MAJOR GENERATOR COMPONENTS