Generac Power Systems 0830890SRV User manual

PRODUCT INFORMATION BULLETIN
for Control Board # 0830890SRV
SUBJECT: C Option Engine Control PCB Adjustment Procedure
MODELS AFFECTED: All generator sets utilizing a C Option control panel.
PROBLEM: Overspeed and starter disengage calibration.
CORRECTIVE ACTION: This adjustment must be done to ensure proper operation.The following
adjustment is for setting the engine OVERSPEED shutdown function.This
adjustment also serves as the starter disengage speed setpoint. If this adjust-
ment is not properly made it could cause damage to the engine or alternator
in an overspeed condition, or to the starter and ring gear if the starter does
not properly disengage.
1. Before starting the generator, turn COARSE adjustment pot full
CLOCKWISE, FINE pot COUNTER-CLOCKWISE.
2. Start engine, make sure engine is up to rated speed.
3. Turn COARSE pot slowly until red LED on PCB board turns on.
4. Turn FINE pot slowly until red LED goes out.
5. Turn FINE pot back slowly until red LED turns back on.
6. Verify proper overspeed shutdown by manually increasing engine speed
until engine shuts down.Verify that engine shutdown occurs at 72 Hz. If
not, slightly adjust FINE pot to achieve proper shutdown speed.This will
also ensure that the starter disengages at approximately 500 rpm.
Replaces PIB02-9-S
MORE DETAILED INSTRUCTIONS on the back page.

1. On the circuit board, locate potentiometers R26 and R27. See Figure 1. Also, locate the
red LED.
2. Turn the COARSE (R26) pot all the way clockwise (CW).
3. Turn the FINE (R27) pot all the way counterclockwise (CCW).
4. Start the generator engine manually, using the Start/Stop switch. Let the engine stabilize
and warm up at no-load. If necessary, adjust the engine
governor to obtain normal rated operating speed.
5. With the unit running at no-load and at its normal rated speed, slowly turn the COARSE
(R26) pot counterclockwise (COW) until the red LED just turns on.
6. Slowly turn the FINE (R27) pot clockwise (CW) until the red LED just goes out.
7. Slowly, turn the FINE (R27) pot counterclockwise (CCW) until the red LED just turns on.
With the board properly calibrated, overspeed shutdown will occur at approximately 10
Hertz above the unit's normal operating frequency. For example, if the engine no-load
speed is 62 Hertz, overspeed shut-down will occur at
approximately 72 Hertz.
MORE DETAILED INSTRUCTIONS from Generac Diagnostic Repair Manual # 79247:
CAUTION: Steps 2 and 3 MUST be completed BEFORE THE ENGINE IS STARTED. If the engine is
started before the steps are completed, an over-speed shutdown may occur at normal rated operating
speed.
PRODUCT INFORMATION BULLETIN
for Control Board # 0830890SRV