TP-6804 12/1124 Section 2 Generator Set Operation
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.
D Oil 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.
2.4.3 Unloaded 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.
2.4.4 Loaded 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.
2.4.5 Power 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.
2.5.1 Warnings
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.
2.5.2 Shutdowns
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.
2.5.3 ATS Communication Errors
When a Model RXT transfer switch is used, an ATS fault
indicates that the connection to the i nterface board on
the transfer switch has been lost. Check the connection
to the ATS interface board.