Section 3 - Operation

Bryant Liquid-cooled 25 kW Generator

3.2MANUAL TRANSFER AND

START-UP

To transfer electrical loads to the Standby (EMER- GENCY) power source side and start the engine man- ually, refer to the Owner’s Manual of the particular transfer switch.

3.3ENGINE GOVERNOR

ADJUSTMENTS

Engine speed governing is also controlled by the engine control board. The engine governor has been set by the factory during final testing of the generator and should not be adjusted.

If, however, adjustments are necessary, the following procedure should be followed (Figure 3.2 and Section 3.8):

1.Move dip switch 8 to the test mode (OFF posi- tion).

2.Set all three potentiometers (pots) fully counter- clockwise.

3.Under no load condition, increase the GAIN pot as much as possible without causing instability.

4.Apply 1/4, 1/2, 3/4 and full load to the unit. Decrease the GAIN pot if there is instability at any load point.

5.Under full load condition, increase the stability pot until the unit returns to 60 Hertz (or 50 Hertz in 50 Hertz applications).

Figure 3.2 — Engine Governor Adjustment

6.Reduce load to 3/4, 1/2, 1/4 and no load. Decrease the stability pot if there is instability at any load point.

7.Adjust differential pot to make the recovery to load changes even faster and minimize load change undershoot and overshoot. If it is set too high, it may introduce oscillations at some load. It can be set to zero (full CCW) if a small amount causes oscillations at some load.

3.4RETRANSFER AND SHUTDOWN

When utility power source voltage has been restored, electrical loads may be transferred back to that source and the generator can be shut down as fol- lows:

Verify that utility power supply voltage to the trans- fer switch has been positively turned Off, using whatever means provided (such as utility main line circuit breaker).

Set the generator’s main circuit breaker to its Off or Open position.

Let the generator engine run at no-load for a few minutes, to stabilize internal unit temperatures.

On the generator console, set the Auto/Off/ Manual switch to Off. Wait for engine to come to a complete stop.

For transfer to utility position, refer to the Owner’s Manual of the particular transfer switch.

Turn on the utility power supply to the transfer switch, using whatever means provided (such as a utility main line circuit breaker). The utility power source now powers the loads.

3.5 AUTOMATIC OPERATION

To set the system for fully automatic operation, pro- ceed as follows:

• Check that load circuits are connected to the utility power supply.

• Set the AUTO/OFF/MANUAL switch to its AUTO position.

• Set the generator main circuit breaker to its ON or CLOSED position.

3.6 WEEKLY EXERCISE CYCLE

The engine control board will start and run the gen- erator once every seven days for approximately 12 minutes. If utility should fail during this exercise period, the engine control board will transfer the load to the generator output and continue to run until util- ity returns.

On the day, and at the time of day chosen for the gen- erator to exercise, set the weekly exercise cycle as fol- lows:

1. Place the AUTO/OFF/MANUAL switch in the auto position (Figure 3.3).

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Bryant ASPAS1BBL025 Manual Transfer START-UP Engine Governor Adjustments, Retransfer and Shutdown, Automatic Operation