HomeControllersDC2 generator set

DC2 generator set Controller

The DC2 generator set is a generator-set controller. It is used on generator sets from Kohler, including the RDC2 or DC2 generator set controller.

3
Generator sets
Kohler
Brand
Bi-Fuel (NG/LP)
Fuel

Generator sets using this controller

3
Kohler RDC2 or DC2 generator set controller

Also fitted to: Kohler 14/20RESA/RESAL, Kohler 20RESC/RESCL.

Engines paired with this controller

2

Troubleshooting

36

Fault codes

CodeMeaningCauseRemedy
BusDeadLiveThe bus is measured to be dead when one of the generators is supposed to be supplying voltage to the bus (closed contactor)Bus metering V9A and V9B connections to V9 of paralleling protection harness are connected incorrectly.
BusLiveDeadThe bus is measured to be live when no generators are connected to it (both contactors open).Bus metering V9A and V9B connections to V9 of paralleling protection harness are connected incorrectly.
CfgModelNumThe two generators that are intended to be paralleled have incompatible model numbers.Incorrect configuration of one of the generators. Different generator types. The paralleled generator sets must be the same kW model. (i.e. two 14 kW or two 20 kW models.)
CfgSysVoltThe system voltage of the two generators intended to be paralleled is not the same.One of the two generators is incorrectly configured. Intermittent connections on RBUS network wiring.
Current A High WarningOver Current ParalleledPress AUTO or OFF *
ErraticSigThe power metering on this controller gives a signal that is not consistent with the system configuration. Reversing the power direction does not resolve the problem.Bad wiring to the CT. Too much tension on wires from the CT to the controller.
Frequency High WarningOver Frequency ParalleledPress AUTO or OFF *
Frequency Low WarningUnder Frequency ParalleledPress AUTO or OFF *
LossOfComAPMThe Automatic Paralleling Module has stopped communicating on RBUS. (An APM was detected on the RBUS network but is no longer communicating.)APM is unplugged. Primary controller is powered down. Check the battery connections. See previous page for more information. Intermittent connections on RBUS network wiring. Check RBUS communication connections.
LossOfComm2The primary controller has lost communication with the secondary controller. (A secondary controller was detected, then communication was lost.)RBUS disconnected, secondary controller battery disconnected, updating firmware in secondary controller, or intermittent RBUS connections.
LossOfFieldThis generator has absorbed more than 25% reactive power (magnetic excitation current) for 20 seconds Generator voltage on this generator is not calibrated correctly. Generator voltage on other generator is not calibrated correctly. Bus voltage on this generator is not calibrated correctly. Bus voltage on the other generator is not calibrated correctly.
MeterUnknownThis generator does not know if the metering is connected or the orientation of the connection. This means that the generators can’t share load accurately until this information is known.System commissioning and startup not yet complete. See the APM instructions.
MeteringOkThe generator has verified that the metering is connected correctly and that the direction is consistent with expected power direction. Status message indicates that the CT is connected to the generator correctly.
NoCurrentThe generator has applied load (using the other generator) and has observed no current on the power sensing inputs.The CT is not connected to the controller. The output leads from the generator do not go through the CT in the correct direction. See the APM instructions.
Reactive Power Low WarningLoss of Field ParalleledPress AUTO or OFF *
Real Power High WarningOver Power ParalleledPress AUTO or OFF *
Real Power Low WarningReverse Power ParalleledPress AUTO or OFF *
SyncFailureThe generator has been attempting to synchronize for over 2 minutes without success.Generator is hunting. Advanced speed control settings need adjustment. Load is changing frequently to disturb the online generator.
Voltage L1-L2 High WarningOver Voltage ParalleledPress AUTO or OFF *
Voltage L1-L2 Low WarningUnder Voltage ParalleledPress AUTO or OFF *

Symptoms & remedies

SymptomCauseRemedy
ATS Status or Configuration menus are not displayed on the RDC2 controllerCheck the RBUS connections from the RDC2 controller on the generator to the interface board on the RXT transfer switch.
ATS settings are not correctly configuredOn systems equipped with the DC2 controller, a personal computer and Kohlerr SiteTecht software must be used to adjust the ATS settings. See Section 4.3.
ATS status and settings are not correctCheck the ATS status and settings. Use the RDC2 controller menus and/or connect a personal computer (PC) to the RDC2 or DC2 controller on the generator set and use the Kohlerr SiteTecht program on your PC.
Application code version number is outdatedCheck the application code version number on the RDC2/DC2 controller. Check TechTools for the latest information about application code updates, and obtain the latest version if necessary.
Battery acid on skinFlush the affected area for 15 minutes with large quantities of clean water and seek medical aid if necessary.
Battery acid splashes in the eyesImmediately flush the affected area for 15 minutes with large quantities of clean water. Seek immediate medical aid.
Battery short circuitsDisconnect the battery before generator set installation or maintenance. Remove all jewelry before servicing the equipment. Use tools with insulated handles. Remove the negative (-) lead first when disconnecting the battery. Reconnect the negative (-) lead last when reconnecting the battery.
Bodily injury and/or equipment damageBattery short circuitsDisconnect the battery before generator set installation or maintenance. Remove all jewelry before servicing the equipment. Use tools with insulated handles. Remove the negative (--) lead first when disconnecting the battery. Reconnect the negative (--) lead last when reconnecting the battery. Never connect the negative (--) battery cable to the positive (+) connection terminal of the starter solenoid. Do not test the battery condition by shorting the terminals together.
Corrosion, loose terminals, damaged wiring or connectorsUnplug connectors and check terminals and leads for corrosion. Remove corrosion from terminals and leads. Tighten loose terminals. Check wiring harnesses for continuity or short circuits. Recrimp or replace loosely connected lead terminals.
Engine does not startLow oil pressure or oil levelCheck and refill oil if necessary. Refer to the 'Oil Check' section for details.
Engine overheatsCoolant level is low or coolant is contaminatedCheck and refill coolant if necessary. Refer to the 'Cooling System' section for details.
Generator produces low voltage outputDirty air filterClean the air filter as per the instructions in the 'Air Cleaner Service' section.
Loose or open connections or short circuits from the RXT interface board to the generator setCheck the connections from the RXT interface board to the generator set for loose or open connections or short circuits.
Optional equipment such as Load Control Module (LCM) is not properly disconnectedDisconnect optional equipment such as the Load Control Module (LCM) and test the ATS operation to isolate problems to the transfer switch or connected accessories.
RDC2 or DC2 controller on the generator set is not in AUTO mode, or engine starting battery is not connected and chargedCheck that the RDC2 or DC2 controller on the generator set is in AUTO mode and that the engine starting battery is connected and charged.
Source circuit breakers/switches to the transfer switch are not closed, or no power source is availableVerify that the source circuit breakers/switches to the transfer switch are closed and at least one power source is available.

Fault codes and symptom→remedy steps extracted from this controller’s service/owner documentation; verify against the official manual before servicing. Aggregated from the service documentation of generator sets built on this controller.