Kohler Troubleshooting Generator ATS Communication Errors and Understanding the DC2 Controller Manual

RDC2/DC2 controller to check the output power for correct voltage, frequency, and stability. When the engine is running at full speed, the controller verifies that the voltage and frequency are within acceptable limits. A fault message is displayed if the voltage or frequency is out of range.

DOil pressure. Oil pressure is verified to ensure proper lubrication of critical engine components. Pressure is monitored at both reduced and full speeds. If the oil pressure is low, the Low Oil Pressure message is displayed and the generator set shuts down.

2.4.3Unloaded Full-Speed Exercise

The unloaded full-speed exercise runs the generator set at full speed for 20 minutes without transferring the load.

To set an unloaded full-speed exercise, follow the procedure in Figure 3-8 and select Exercise Mode: Unloaded Full.

2.4.4Loaded Full-Speed Exercise (with RXT only)

A loaded exercise starts the generator set, ramps up to full speed, and then transfers the electrical load from the utility source to the generator set. After 20 minutes, the load is transferred back to the utility source. The engine runs without load for 5 minutes or until cool, and then shuts down automatically.

Note: With a loaded exercise, power to the building is lost for up to 10 seconds during load transfer.

For a loaded exercise controlled by the RDC2 or DC2 controller, a Model RXT transfer switch must be connected to the generator set. To set a loaded exercise, follow the procedure in Figure 3-8 and select Exercise Type: Loaded.

For a loaded exercise with a transfer switch other than a Kohlerr Model RXT, program the exercise at the transfer switch controller. Refer to the transfer switch operation manual for instructions.

2.4.5Power Failure During Exercise Cycle

If the utility power is lost during an unloaded exercise, the ATS transfers to the emergency source, the exercise is ended and the control remains in the AUTO mode.

If the utility power is lost during a loaded exercise, the exercise is ended. The ATS remains in the emergency position and the control goes into the AUTO mode.

The generator set continues to run and supply power to the load for the duration of the utility power outage. When Utility power is restored, the ATS will re-transfer to the utility source through normal timing sequences.

2.5 Faults

The RDC2/DC2 controller displays fault messages for generator set warnings and shutdowns. Selected fault messages are shown in Figure 2-3.

2.5.1Warnings

The controller displays a fault message but the generator set does not shut down on a warning. The controller resets automatically after a warning condition is corrected.

2.5.2Shutdowns

Under a fault shutdown condition, the generator set shuts down automatically and the controller displays a fault message. The OFF LED flashes. In some cases, the engine cooldown cycle runs before the engine shuts down. See Figure 2-3.

Shutdown switches (such as the low oil pressure switch or high engine temperature switch) on the generator set will automatically reset when the problem is corrected. However, the fault condition at the controller does not clear until the controller is reset.

The generator set cannot be restarted until the fault condition is corrected and the controller is reset. See Section 2.5.4 for instructions to reset the controller after a fault shutdown.

2.5.3ATS Communication Errors

When a Model RXT transfer switch is used, an ATS fault indicates that the connection to the interface board on the transfer switch has been lost. Check the connection to the ATS interface board.

24 Section 2 Generator Set Operation TP-6804 12/11