Single Plant Operation

Connecting an electric plant to a de-energized bus involves two general phases: (1) starting the diesel engine and bringing it up to rated speed under control of the governor and (2) operating the switchboard controls to bring the power of the generator onto the bus.

Different manufacturers of generating plants require the operator to perform a multitude of steps before starting the prime mover. For example, if a diesel engine is started by compressed air, the operator would have to align the compressed air system. This would not be necessary if the engine is of the electric-start type. It's important that you, as the plant supervisor, establish a prestart checklist for each generating plant. The prestart checklist provides a methodical procedure for confirming the operational configuration of the generating plant; following this procedure assures that all systems and controls are properly aligned for operation.

The checklist should include, but is not limited to, the following:

1. Align ventilation louvers.

2. Check lube oil, fuel oil, and cooling water levels.

3. Ensure battery bank is fully charged.

4. Align electrical breakers and switches for proper operation of auxiliary equipment.

5. Check control panel and engine controls.

6. Select the proper operating position for the following controls for single plant operation.

Voltage regulator switch to UNIT or SINGLE position.

Governor switch to ISOCHRONOUS or SINGLE position. NOTE: Adjust hydraulic governor droop position to 0.

Voltage regulator control switch to AUTO position.

The prestart checklist should be completed in sequence before you attempt to start the generating plant.

Start the generating plant and adjust engine rpm to synchronous speed. Adjust the voltage regulator to obtain the correct operating voltage. Set the synchronizing switch to the ON position and close the main circuit breaker. Adjust the frequency to 60 hertz with the governor control switch. Perform hourly operational checks to detect abnormal conditions and to ensure the generating set is operating at the correct voltage and frequency.