TP-6905 9/21
18 Section 2 Generator Set Operation
If a transfer switch other than the Model RXT is used, an
additional engine cooldown time delay may be
programmed on the transfer switch. To allow the smart
engine cooldown on the RDC2 controller to operate
most efficiently, set the cooldown time on the transfer
switch controller to zero or the minimum time allowed.
Refer to the instructions provided with the transfer
switch for more information.
2.4.6
Automatic Operation with Model
RXT Transfer Switch
The Model RXT transfer switch connects to the RDC2
controller through the ATS interface board on the
transfer switch. Also see Section 2.7, Model RXT
Transfer Switch Operation.
The RDC2 controller must be in AUTO mode for
automatic transfer switch operation.
Automatic Start
The RDC2 controller receives utility source voltage
sensing data from the Model RXT transfer switch.
1. If the utility source voltage falls below an
acceptable level, the controller starts the engine
start time delay.
2. If the utility source is not restored before the time
delay expires, the generator set starts.
3. After the Normal-to-Emergency time delay, the
ATS is signaled to transfer the load to the
emergency source.
Automatic Stop
1. When the utility source is restored, the
Emergency-to-Normal time delay starts.
2. When the Emergency-to-Normal time delay
expires, the load is transferred to the utility.
3. The generator set stops.
2.4.7
Automatic Operation with Other
Transfer Switches
If a Kohler Model RDT transfer switch is used, the
engine start contacts from the ATS must be connected
to engine start leads 3 and 4 on the generator set.
The RDC2 generator set controller must be in AUTO
mode to respond to remote start/stop signals from an
ATS or remote switch. Press the AUTO button on the
RDC2 controller to put the generator set into automatic
mode.
Automatic Start
The engine start contacts on the ATS close to signal the
generator set to start, and remain closed while the
generator set is running.
Automatic Stop
The engine start contacts on the ATS open to signal the
generator set to stop.