Use and Care Manual

TP-6810 6/15 19Section 2 Generator Set Operation
D Ramps down and runs at reduced speed for
5 minutes to cool down the engine before shutting
down automatically.
Engine Speed, RPM
Engine
Exercise
Full-Speed
Diagnostics
Cooldown
3min.
1min.
1min.
10 min. 5 min.
Figure 2-1 Unloaded Exercise Cycle
System Diagnostics
During the unloaded cycle exercise, the controller
monitors the following data. The controller display
indicates an unloaded exercise run during the
diagnostics, unless a fault is detected as described
below.
D ATS connection. The controller verifies that the
Model RXT ATS interface board is connected.
D Battery voltage. Battery voltage is checked before
exercise to verify engine starting capability. Battery
voltage provides a measurement of battery health. If
the controller detects low battery voltage, low battery
or low charging battery is displayed and the exercise
does not start.
D Coolant level check. The coolant level is checked.
D Communication integrity tests. J1939, RBUS,
Ethernet, and USB are monitored for messages
indicating that the controller and wiring are reliable.
D Engine speed. Engine speed is measured at low
speed and full speed. An overspeed or underspeed
condition will result in a fault condition and shutdown.
D Generator output frequency and voltage.
Operating the generator at full speed allows the
RDC2 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 low and full speeds. If
the oil pressure is low, low oil pressure is displayed
and the generator set shuts down.
2.5.2 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 2-3 and select Exercise Mode:
Unloaded Full.
2.5.3 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. The load is
transferred back to the utility source before the
generator set shuts down.
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 controller,
a Model RXT transfer switch must be connected to the
generator set. To set a loaded exercise, follow the
procedure in Section 2.5.8 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.
2.5.4 Shutdown During Exercise
The following advanced diagnostic operation applies to
RDC2 controllers with firmware versions 5.04 and
higher.
If the generator set shuts down on a fault during an
exercise, the controller will try to restart the engine. If the
engine starts, the generator set will run at full speed for
two minutes and then stop. The event history will show
Advanced Diagnostic Active. The exercise schedule is
maintained.
If the engine does not start, the shutdown message will
be displayed. Correct the fault condition and reset the
fault as described in Section 2.6.