Kohler 14RCA User manual

Models:
14RCA
14RCAL
18RCAL
20RCA
20RCAL
Controller:
RDC2
Residential/Commercial Generator Sets
TP-7092 11/22b
Operation

2 TP-7092 11/22
WARNING: This product can expose you to chemicals, including carbon monoxide and
benzene, which are known to the State of California to cause cancer and birth defects or
other reproductive harm. For more information go to www.P65warnings.ca.gov
Kohler strongly recommends that only factory-
authorized dealers install and service the generator.
Product Identification Information
Product identification numbers determine service parts. Record the product identification numbers in the spaces below
immediately after unpacking the products so that the numbers are readily available for future reference. Record field-installed
kit numbers after installing the kits.
Generator Set Identification Numbers
Record the product identification numbers from the generator set nameplate(s).
Model Designation _________________________________________________________
Specification Number _______________________________________________________
Serial Number: ____________________________________________________________
Controller Identification
Record the controller description from the generator set operation manual, spec sheet, or sales invoice.
Controller Description________________________________________________________
Engine Identification
Record the product identification information from the engine nameplate.
Manufacturer_________________________________________________________________
Model Designation___________________________________________________________
Serial Number_______________________________________________________________
Accessory Number
Accessory Description
Accessory Number
Accessory Description

TP-7092 11/22 3
Table of Contents
Safety Precautions and Instructions ........................................................................................................................................7
Introduction ..............................................................................................................................................................................13
Service Assistance...................................................................................................................................................................16
Section 1. Descriptions and Service Views...........................................................................................................17
1.1 Introduction ............................................................................................................................................................17
1.2 Engine....................................................................................................................................................................17
1.3 Alternator................................................................................................................................................................17
1.4 Generator Set Enclosure........................................................................................................................................17
1.5 Transfer Switch......................................................................................................................................................17
1.6 Controller................................................................................................................................................................18
1.7 OnCue® Plus Generator Management System .....................................................................................................20
1.8 Accessories............................................................................................................................................................20
1.8.1 Cold Weather Package Kit.......................................................................................................................20
1.8.2 Battery Heater Kit.....................................................................................................................................20
1.8.3 Breather Tube Heater and Oil Heater Kit.................................................................................................21
1.8.4 Fuel Regulator Heater (18 and 20kW models only).................................................................................22
1.8.5 Oil Pressure Sensor Boot Kit ...................................................................................................................23
1.8.6 Carburetor Heater....................................................................................................................................23
1.8.7 Emergency Stop Kit.................................................................................................................................24
1.8.8 Load Management...................................................................................................................................24
1.8.9 PowerSync Automatic Paralleling Module (APM) ....................................................................................24
1.8.10 Programmable Interface Module (PIM)....................................................................................................25
1.9 Service Views.........................................................................................................................................................26
Section 2. Generator Set Operation .......................................................................................................................27
2.1 Prestart Checklist...................................................................................................................................................27
2.2 Exercising the Generator Set.................................................................................................................................27
2.3 Generator Set Operation........................................................................................................................................27
2.3.1 Local Starting and Stopping.....................................................................................................................28
2.3.2 Automatic Operation................................................................................................................................28
2.3.3 Remote Starting and Stopping.................................................................................................................28
2.3.4 Remote Emergency Stop Switch .............................................................................................................28
2.3.5 Engine Start Crank Cycle.........................................................................................................................30
2.3.6 Engine Cooldown.....................................................................................................................................30
2.3.7 Automatic Operation with Model RXT Transfer Switch............................................................................30
2.3.8 Automatic Operation with Other Transfer Switches .................................................................................30
2.4 Exercise .................................................................................................................................................................31
2.4.1 Setting the Exerciser................................................................................................................................31
2.4.2 Unloaded Cycle Exercise with Complete System Diagnostics.................................................................32
2.4.3 Unloaded Full-Speed Exercise.................................................................................................................33
2.4.4 Loaded Full-Speed Exercise (with RXT only)...........................................................................................33
2.4.5 Shutdown During Exercise (Advanced Diagnostic)..................................................................................33
2.4.6 Power Failure During Exercise Cycle.......................................................................................................33
2.5 Faults .....................................................................................................................................................................34
2.5.1 Warnings..................................................................................................................................................34
2.5.2 Shutdowns...............................................................................................................................................34
2.5.3 Shutdown During Exercise (Advanced Diagnostic)..................................................................................34
2.5.4 ATS Communication Errors .....................................................................................................................34
2.5.5 Resetting the Controller After a Fault Shutdown......................................................................................34
2.5.6 Faults Related to Paralleling....................................................................................................................37

4 TP-7092 11/22
Section 3. RDC2 Controller Operation ...................................................................................................................39
3.1 RDC2 Generator Set/Transfer Switch Controller....................................................................................................39
3.2 Control and Indicators............................................................................................................................................39
3.2.1 Controller Keypad....................................................................................................................................40
3.2.2 LED Indicators .........................................................................................................................................41
3.2.3 LCD Display.............................................................................................................................................41
3.3 Controller Power.....................................................................................................................................................42
3.4 Battery Charging....................................................................................................................................................42
3.5 Changing Settings..................................................................................................................................................43
3.6 Setting the Exerciser..............................................................................................................................................45
3.6.1 Setting the Exerciser at Controller Power-up...........................................................................................45
3.6.2 Changing the Exercise Settings...............................................................................................................45
3.7 RDC2 Controller Menus .........................................................................................................................................47
3.8 Main Menu .............................................................................................................................................................47
3.9 Overview Menu......................................................................................................................................................48
3.10 Engine Metering Menu...........................................................................................................................................49
3.11 Generator Metering Menu......................................................................................................................................50
3.12 Generator Set Information Menu............................................................................................................................51
3.13 Genset Run Time Menu.........................................................................................................................................51
3.14 Genset System Menu.............................................................................................................................................52
3.15 ATS Status Menu...................................................................................................................................................54
3.16 ATS Configuration Menu........................................................................................................................................55
3.17 Date and Time Menu..............................................................................................................................................56
3.18 Networking Information Menus...............................................................................................................................56
3.18.1 Networking Status Submenu....................................................................................................................57
3.18.2 Networking Configuration Submenu (OnCue® Password) ......................................................................58
3.18.3 RBUS Information....................................................................................................................................60
3.18.4 Remote Devices Submenu ......................................................................................................................61
3.19 Programmable Interface Module (PIM) Status Menu .............................................................................................62
3.20 Load Control Menus...............................................................................................................................................63
3.21 Event Log...............................................................................................................................................................64
Section 4. Scheduled Maintenance ........................................................................................................................65
4.1 Scheduled Maintenance.........................................................................................................................................65
4.1.1 Service Schedule, 14 kW Models ............................................................................................................66
4.1.2 Service Schedule, 18 and 20 kW Models.................................................................................................67
4.2 Lubrication System.................................................................................................................................................68
4.2.1 Low Oil Pressure Shutdown.....................................................................................................................68
4.2.2 Oil Check .................................................................................................................................................69
4.2.3 Engine Oil Recommendation ...................................................................................................................69
4.2.4 Oil Change Procedure..............................................................................................................................69
4.2.5 Resetting the Maintenance Timer............................................................................................................71
4.2.6 Oil Cooler (18/20RCA/RCAL only)...........................................................................................................71
4.3 Spark Plugs............................................................................................................................................................72
4.4 Air Cleaner Service ................................................................................................................................................73
4.4.1 Air Cleaner, 14 kW Models ......................................................................................................................73
4.4.2 Air Cleaner, 18/20 kW Models .................................................................................................................74
4.5 Cooling System......................................................................................................................................................75
4.6 Exhaust System.....................................................................................................................................................75
4.7 Battery....................................................................................................................................................................76
4.7.1 Cleaning the battery.................................................................................................................................77
4.7.2 Checking Electrolyte Level.......................................................................................................................77
4.7.3 Checking Specific Gravity........................................................................................................................77

TP-7092 11/22 5
4.8 Storage Procedure.................................................................................................................................................79
4.8.1 Lubricating System ..................................................................................................................................79
4.8.2 Fuel System.............................................................................................................................................79
4.8.3 Cylinder Lubrication.................................................................................................................................79
4.8.4 Exterior Preparation.................................................................................................................................79
4.8.5 Battery......................................................................................................................................................79
Section 5. Troubleshooting.....................................................................................................................................81
5.1 Introduction ............................................................................................................................................................81
5.2 Fault Messages......................................................................................................................................................81
5.3 Circuit Protection....................................................................................................................................................81
5.3.1 Controller Internal Circuit Protection ........................................................................................................81
5.3.2 Line Circuit Breaker..................................................................................................................................81
5.4 USB Port and Auxiliary Winding Mini-Breaker........................................................................................................81
5.5 Stop Switches.........................................................................................................................................................82
5.6 Thermostat.............................................................................................................................................................82
5.7 Troubleshooting......................................................................................................................................................84
Appendix A. Abbreviations.........................................................................................................................................85

6 TP-7092 11/22

TP-7092 11/22 7
Safety Precautions and Instructions
IMPORTANT SAFETY INSTRUCTIONS. Electromechanical equipment, including generatorsets, transfer switches, switchgear,
and accessories, can cause bodily harm and pose life-threatening danger when improperly installed, operated, or maintained.
To prevent accidents be aware of potential dangers and act safely. Read and follow all safety precautions and instructions.
SAVE THESE INSTRUCTIONS.
This manual has several types of safety precautions and instructions: Danger, Warning, Caution, and Notice.
DANGER
DANGER indicates a hazardous situation which, if not avoided, will result in death or serious injury.
WARNING
WARNING indicates a hazardous situation which, if not avoided, could result in death or serious injury.
CAUTION
CAUTION indicates a hazardous situation which, if not avoided, could result in minor or moderate injury.
NOTICE
NOTICE is used to address practices not related to physical injury.
Safety decals affixed to the equipment in prominent places alert the operator or service technician to potential hazards and
explain how to act safely. The decals are shown throughout this publication to improve operator recognition. Replace missing or
damaged decals.
Accidental Starting
WARNING
Accidental starting.
Can cause severe injury or death.
Disconnect the battery cables before working on the generator set. Remove the
negative (–) lead first when disconnecting the battery. Reconnect the negative (–)
lead last when reconnecting the battery.
Disabling the generator set. Accidental starting can cause severe injury or death. Before working on the generator set or
equipment connected to the set, disable the generator set as follows: (1) Press the generator set off/reset button to shut down
the generator set. (2) Disconnect the power to the battery charger, if equipped. (3) Remove the battery cables, negative (–) lead
first. Reconnect the negative (–) lead last when reconnecting the battery. Follow these precautions to prevent the starting of the
generator set by the remote start/stop switch.

8 TP-7092 11/22
Battery
WARNING
Sulfuric acid in batteries.
Can cause severe injury or death.
Wear protective goggles and clothing. Battery acid may cause blindness and burn skin.
WARNING
Explosion.
Can cause severe injury or death.
Relays in the battery charger cause arcs or sparks.
Locate the battery in a well‐ventilated area. Isolate the battery charger from explosive
fumes.
Battery electrolyte is a diluted sulfuric acid. Battery acid can cause severe injury or death. Battery acid can cause
blindness and burn skin. Always wear splashproof safety goggles, rubber gloves, and boots when servicing the battery. Do not
open a sealed battery or mutilate the battery case. If battery acid splashes in the eyes or on the skin, immediately flush the
affected area for 15 minutes with large quantities of clean water. Seek immediate medical aid in the case of eye contact. Never
add acid to a battery after placing the battery in service, as this may result in hazardous spattering of battery acid.
Battery acid cleanup. Battery acid can cause severe injury or death. Battery acid is electrically conductive and corrosive.
Add 500 g (1 lb.) of bicarbonate of soda (baking soda) to a container with 4 L (1 gal.) of water and mix the neutralizing solution.
Pour the neutralizing solution on the spilled battery acid and continue to add the neutralizing solution to the spilled battery acid
until all evidence of a chemical reaction (foaming) has ceased. Flush the resulting liquid with water and dry the area.
Battery gases. Explosion can cause severe injury or death. Battery gases can cause an explosion. Do not smoke or permit
flames or sparks to occur near a battery at any time, particularly when it is charging. Do not dispose of a battery in a fire. To
prevent burns and sparks that could cause an explosion, avoid touching the battery terminals with tools or other metal objects.
Remove all jewelry before servicing the equipment. Discharge static electricity from your body before touching batteries by first
touching a grounded metal surface away from the battery. To avoid sparks, do not disturb the battery charger connections while
the battery is charging. Always turn the battery charger off before disconnecting the battery connections. Ventilate the
compartments containing batteries to prevent accumulation of explosive gases.
Battery short circuits. Explosion can cause severe injury or death. Short circuits can cause bodily injury and/or equipment
damage. Disconnect 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.

TP-7092 11/22 9
Engine Backfire/Flash Fire
WARNING
Risk of fire.
Can cause severe injury or death.
Do not smoke or permit flames or sparks near fuels or the fuel system.
Servicing the fuel system. A flash fire can cause severe injury or death. Do not smoke or permit flames or sparks near the
carburetor, fuel line, fuel filter, fuel pump, or other potential sources of spilled fuels or fuel vapors. Catch fuels in an approved
container when removing the fuel line or carburetor.
Servicing the air cleaner. A sudden backfire can cause severe injury or death. Do not operate the generator set with the
air cleaner removed.
Combustible materials. A fire can cause severe injury or death. Generator set engine fuels and fuel vapors are flammable
and explosive. Handle these materials carefully to minimize the risk of fire or explosion. Equip the compartment or nearby area
with a fully charged fire extinguisher. Select a fire extinguisher rated ABC or BC for electrical fires or as recommended by the
local fire code or an authorized agency. Train all personnel on fire extinguisher operation and fire prevention procedures.
Exhaust System
WARNING
Carbon monoxide.
Can cause severe nausea, fainting, or death.
The exhaust system must be leakproof and routinely inspected.
Generator set operation. Carbon monoxide can cause severe nausea, fainting, or death. Carbon monoxide is an odorless,
colorless, tasteless, nonirritating gas that can cause death if inhaled for even a short time. Avoid breathing exhaust fumes when
working on or near the generator set. Never operate the generator set inside a building unless the exhaust gas is piped safely
outside. Never operate the generator set where exhaust gas could accumulate and seep back inside a potentially occupied
building.
Carbon monoxide detectors. Carbon monoxide can cause severe nausea, fainting, or death. Install carbon monoxide
detectors on each level of any building adjacent to the generator set. Locate the detectors to adequately warn the building’s
occupants of the presence of carbon monoxide. Keep the detectors operational at all times. Periodically test and replace the
carbon monoxide detectors according to the manufacturer’s instructions.
Carbon monoxide symptoms. Carbon monoxide can cause severe nausea, fainting, or death. Carbon monoxide is a
poisonous gas present in exhaust gases. Carbon monoxide is an odorless, colorless, tasteless, nonirritating gas that can cause
death if inhaled for even a short time. Carbon monoxide poisoning symptoms include but are not limited to the following:
•Light-headedness, dizziness
•Physical fatigue, weakness in joints and muscles
•Sleepiness, mental fatigue, inability to concentrate or speak clearly, blurred vision
•Stomachache, vomiting, nausea
If experiencing any of these symptomsand carbon monoxide poisoningis possible, seek fresh airimmediately and remain active.
Do not sit, lie down, or fall asleep. Alert others to the possibility of carbon monoxide poisoning. Seek medical attention if the
condition of affected persons does not improve within minutes of breathing fresh air.

10 TP-7092 11/22
Fuel System
WARNING
Explosive fuel vapors.
Can cause severe injury or death.
Use extreme care when handling, storing, and using fuels.
The fuel system. Explosive fuel vapors can causesevere injury or death. Vaporized fuels are highly explosive. Use extreme
care when handling and storing fuels. Store fuels in a well-ventilated area away from spark-producing equipment and out of the
reach of children. Never add fuel to the tank while the engine is running because spilled fuel may ignite on contact with hot parts
or from sparks. Do not smoke or permit flames or sparks to occur near sources of spilled fuel or fuel vapors. Keep the fuel lines
and connections tight and in good condition. Do not replace flexible fuel lines with rigid lines. Use flexible sections to avoid fuel
line breakage caused by vibration. Do not operate the generator set in the presence of fuel leaks, fuel accumulation, or sparks.
Repair fuel systems before resuming generator set operation.
Gas fuel leaks. Explosive fuel vapors can cause severe injury or death. Fuel leakage can cause an explosion. Check the
LPG vapor or natural gas fuel system for leakage by using a soap and water solution with the fuel system test pressurized to 6–
8 ounces per square inch (10–14 inches water column). Do not use a soap solution containing either ammonia or chlorine
because both prevent bubble formation. A successful test depends on the ability of the solution to bubble.
Hazardous Noise
CAUTION
Hazardous noise.
Can cause hearing loss.
Never operate the generator set without a muffler or with a faulty exhaust system.
Engine noise. Hazardous noise can cause hearing loss. Generator sets not equipped with sound enclosures can produce
noise levels greater than 105 dBA. Prolonged exposure to noise levels greater than 85 dBA can cause permanent hearing loss.
Wear hearing protection when near an operating generator set.

TP-7092 11/22 11
Hazardous Voltage/Moving Parts
DANGER
Hazardous voltage.
Will cause severe injury or death.
This equipment must be installed and serviced by qualified electrical personnel.
DANGER
Hazardous voltage. Moving parts.
Will cause severe injury or death.
Operate the generator set only when all guards and electrical enclosures are in place.
WARNING
Hazardous voltage. Backfeed to the utility system.
Can cause property damage, severe injury, or death.
If the generator set is used for standby power, install an automatic transfer switch to
prevent inadvertent interconnection of standby and normal sources of supply.
Grounding electrical equipment. Hazardous voltage will cause severe injury or death. Electrocution is possible whenever
electricity is present. Ensure you comply with all applicable codes and standards. Electrically ground the generator set and
related equipment and electrical circuits. Turn off the main circuit breakers of all power sources before servicing the equipment.
Never contact electrical leads or appliances when standing in water or on wet ground because these conditions increase the
risk of electrocution.
CAUTION
Welding the generator set.
Can cause severe electrical equipment damage.
Welding on generator set will cause serious damage to engine electronic controls components. Disconnect all engine electronic
control connections before welding.
Welding on the generator set. Can cause severe electrical equipment damage. Before welding on thegeneratorset perform
the following steps: (1) Remove the battery cables, negative (–) lead first. (2) Disconnect all engine electronic control module
(ECM) connectors. (3) Disconnect all generator set controller and voltage regulator circuit board connectors. (4) Disconnect the
engine battery-charging alternator connections. (5) Attach the weld ground connection close to the weld location.
Connecting the battery and the battery charger. Hazardous voltage will cause severe injury or death. Reconnect the
battery correctly, positive to positive and negative to negative, to avoid electrical shock and damage to the battery charger and
battery(ies). Have a qualified electrician install the battery(ies).
Short circuits. Hazardous voltage/current will cause severe injury or death. Short circuits can cause bodily injury and/or
equipment damage. Do not contact electrical connections with tools or jewelry while making adjustments or repairs. Remove all
jewelry before servicing the equipment.
Electrical backfeed to the utility. Hazardous backfeed voltage can cause severe injury or death. Install a transfer switch
in standby power installations to prevent the connection of standby and other sources of power. Electrical backfeed into a utility
electrical system can cause severe injury or death to utility personnel working on power lines.

12 TP-7092 11/22
Heavy Equipment
WARNING
Unbalanced weight.
Improper lifting can cause severe injury or death and equipment damage.
Do not use lifting eyes. Lift the generator set using lifting bars inserted through the lifting
holes on the skid.
Hot Parts
WARNING
Hot engine and exhaust system.
Can cause severe injury or death.
Do not work on the generator set until it cools.
Servicing the exhaust system. Hot parts can cause severe injury or death. Do not touch hot engine parts. The engine and
exhaust system components become extremely hot during operation.
Servicing the engine heater. Hot parts can cause minor personal injury or property damage. Install the heater before
connecting it to power. Operating the heater before installation can cause burns and component damage. Disconnect power to
the heater and allow it to cool before servicing the heater or nearby parts.
NOTICE
Canadian installations only. For standby service connect the output of the generator set to a suitably rated transfer switch in
accordance with Canadian Electrical Code, Part 1.

TP-7092 11/22 13
Introduction
This manual provides operation and maintenance instructions for Residential/Commercial Model 14RCA/RCAL, 20RCA/RCAL.
and 18RCAL generator sets equipped with the RDC2 generator set/transfer switch controller. See Figure 1.
RCAL models are shipped with a Kohler model RXT Automatic Transfer Switch (ATS). The ATS Operation/Installation Manuals
are included with the transfer switch.
Kohler strongly recommends that only factory authorized dealers install and service the generator.
Have the generator set installed outdoors by an authorized dealer or service technician. Refer to the Installation Manual for
installation instructions. Do not install or operate the generator set indoors.
Information in this publication represents data available at the time of print. Kohler Co. reserves the right to change this
publication and the products represented without notice and without any obligation or liability whatsoever.
Read this manual and carefully follow all procedures and safety precautions to ensure proper equipment operation and to avoid
bodily injury. Read and follow the Safety Precautions and Instructions section at the beginning of this manual. Keep this manual
with the equipment for future reference.
The equipment service requirements are very important to safe and efficient operation. Inspect the parts often and perform
required service at the prescribed intervals. Obtain service from an authorized service dealerto keep equipmentin topcondition.
Figure 1 Generator Set
aac11780

14 TP-7092 11/22
List of Related Literature
Figure 2 identifies literature available for the generator sets and related accessories covered in this manual. Only trained and
qualified personnel should install or service the generator set.
Generator Set Literature
Literature Part No.
Specification Sheet, 14RCA/L
G4-270
Specification Sheet, 18RCAL
G4-313
Specification Sheet, 20RCA/L
G4-272
Installation Manual, Generator Set
TP-7091
Operation Manual, Generator Sets
TP-7092
Warranty Registration and Controller Unlock Code
TP-7238
Service Manual, Generator Set
TP-7093
Transfer Switch Literature
Operation/Installation Manual, Model RDT Transfer Switch
TP-7192
Operation/Installation Manual, Model RXT Automatic Transfer Switch
TP-7193
Accessory Literature
User Guide, OnCue©Plus
TP-7006
Technical Manual, OnCue©Plus
TP-7007
Operation Manual, SiteTech™Software
TP-6701
Firmware Update Using the USB Utility
TT-1636
Accessory Installation Instructions
Carburetor Heater Kit, 14 kW Models
TT-1297
Carburetor Heater Kit 18/20 kW Modela
TT-1482
Fuel Regulator Heater Kit
TT-1569
Programmable Interface Module (PIM)
TT-1584
PowerSync®Automatic Paralleling Module (APM)
TT-1596
Load Shed Kit
TT-1609
Battery Heater Kit
TT-1634
Power Relay Modules
TT-1646
Breather Tube Heater and Oil Heater
TT-1709
Oil Pressure Sensor Boot Kit
TT-1717
OnCue Plus Wireless Kit
TT-1721
Remote Emergency Stop Switch (Lockable)
TT-1795
Figure 2 Related Literature

TP-7092 11/22 15
Nameplate
The following illustration shows a typical generator set nameplate. Copy the model, serial, and specification numbers from the
nameplate into the spaces provided in the product information section on the inside front cover of this manual. See the service
views section for the nameplate location.
Figure 3 Typical Nameplate
Emission Information
The Kohler®Model CH740 engine used on the 14RCA/RCAL generator set is certified to operate using natural gas or propane
fuel.
The Kohler®Model CH1000 engine used on the 18RCAL and 20RCA/RCAL generator sets is certified to operate using natural
gas or propane fuel for emergency standby use only. This generator set is certified by the U.S.EPA for emergency standby
operation backing up a reliable utility source. Operation outside these guidelines is a violation of national EPA regulations.
The Emission Compliance Period referred to on the Emission Control or Air Index label indicates the number of operating hours
for which the engine has been shown to meet CARB or EPA emission requirements. Figure 4 provides the engine compliance
period (in hours) associated with the category descriptor, which may be found on the certification label.
Emission Compliance Period
EPA
Category C
250 hours
Category B
500 hours
Category A
1000 hours
CARB
Moderate
125 hours
Intermediate
250 hours
Extended
500 hours
Figure 4 Emission Compliance Period
Refer to the certification label for engine displacement.
The exhaust emission control system for the CH740 engines (14RCA/L) is EM for U.S. EPA, California, and Europe.
The exhaust emissioncontrol system forthe CH1000 engine (18RCAL and20RCA/L) is EM for U.S. EPA, California, and Europe.
GM12070
ServiceDuty
Voltage
Alt Model
Insulation
MFGDate
Amps
Phase
RPM
Battery
Fuel
kW
kVA
PF
Hz
Genset Model
SpecNumber
Serial Number
Material Number

16 TP-7092 11/22
Generator Set Application
Kohler®Co. ensures that all Kohler®generator sets are certified to applicable standards for their intended application. It is the
owner/operator’s responsibility to operate Kohler®generator sets exclusively according to the directions provided in the
accompanying operation manuals.
Kohler®generator sets designated as Stationary Standby, Emergency or Emergency Standby may only be operated for
emergency power generation and for maintenance/testing. Emergency power generation is limited to power production when
electric power from a local utility (or the normal power source, if the facility runs on its own power production) is interrupted.
Stationary non-emergency application of a Standby, Emergency, or Emergency Standby rated generator set is not allowed.
The U.S.Clean AirAct explicitly prohibits using EmergencyStandby generatorsets as aprimary electric power source regardless
of whether a site is connected to the electrical grid. Emergency Standby generators may NOT be used to power sites which are
not connected to an electric utility.
Owners/operators must ensure that the generator is operated, exercised, and maintained according to this operation manual.
Owners/operators must retain maintenance records.
Service Assistance
For professional advice and conscientious service, please contact your nearest Kohler dealer.
•Visit the Kohler Co. website at KOHLERPower.com.
•Look at the labels and decals on your Kohler product or review the appropriate literature or documents
included with the product.
•Call toll free in the US and Canada 1-800-544-2444.

TP-7092 11/22 17
Section 1. Descriptions and Service Views
1.1 Introduction
The generator set specification sheets provide specific generator and engine information. Refer to the spec sheet for data not
supplied in this manual. Consult the generator set service manual, engine operation manual, and engine service manual for
additional specifications. Obtain copies of the latest spec sheets, manuals, diagrams, and drawings from your local dealer.
1.2 Engine
The generator set has a four-cycle, twin cylinder, air-cooled Kohler®engine. The engine operates on clean-burning natural gas
or LPG. Engine features include:
•Efficient overhead valve design and full pressure lubrication for maximum power, torque, and reliability under all
operating conditions.
•Dependable, maintenance-free electronic ignition.
•Precision-formulated cast iron construction of parts subjected to the most wear and tear.
•Field-convertible multi-fuel systems that allow fuel changeover from natural gas to LPG (and vice-versa) while
maintaining emission certification.
•Digital spark advance optimizes ignition timing for the selected fuel.
1.3 Alternator
The generator uses Kohler’s unique PowerBoost™ voltage regulation system, which provides instant response to load changes.
PowerBoost™ensures reliable motor starting and consistent voltage levels. PowerBoost™utilizes a voltage excitation system
that employs a winding independent of the main output windings to provide excitation voltage.
1.4 Generator Set Enclosure
The generator set is housed in an aluminum enclosure with our fade-, scratch-, and corrosion-resistant Kohler®Power Armor™
automotive-grade textured cashmere finish. The enclosure has a hinged, locking roof that allows easy access to the generator
set controller when required, but locks securely to prevent unauthorized access.
To open the roof, insert the key provided with the enclosure and turn counterclockwise ¼ turn. Then just raise the roof. The roof
stays open until you are ready to close it.
Be sure to close and lock the enclosure, and keep the key in a secure location.
1.5 Transfer Switch
The RDC2 controller is designed to interface with and control the Kohler Model RXT Automatic Transfer Switch (ATS).
If the power system uses a different model transfer switch, the RDC2 controller will not control the transfer switch. An ATS other
than the Model RXT must be equipped with a transfer switch controller and engine start contacts that connect to the remote
engine start terminals on the generator set.

18 TP-7092 11/22
1.6 Controller
RCA and RCAL models are equipped with the RDC2 controller. See Figure 5.
The controller provides integrated control for the generator set, Kohler®Model RXT transfer switch, programmable interface
module (PIM) and load management devices.
The controller’s 2-line LCD screen displays status messages and system settings that are clear and easy to read, even in direct
sunlight or low light.
Figure 5 RDC2 Generator Set Controller
RDC2 Controller Features
•Six-button keypad
oOFF, AUTO, and RUN pushbuttons
oSelect and arrow buttons for access to system configuration and adjustment menus
•LED indicators for OFF, AUTO, and RUN modes
•LED indicators for utility power and generator set source availability and ATS position (Model RXT transfer switch
required)
•LCD display
oTwo lines x 16 characters per line
oBacklit display with adjustable contrast for excellent visibility in all lighting conditions
•Scrolling system status display
oGenerator set status
oVoltage and frequency
oEngine lube oil temperature
oOil pressure
oBattery voltage
oEngine runtime hours
•Date and time displays
•Smart engine cooldown senses engine temperature
•Digital isochronous governor to maintain steady-state speed at all loads

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•Digital voltage regulation: ±0.5% RMS no-load to full-load
•Automatic start with programmed cranking cycle
•Programmable exerciser can be set to start automatically on any future day and time, and run every week or every two
weeks
•Exercise modes
oUnloaded cycle exercise with complete system diagnostics
oUnloaded full-speed exercise
oLoaded full-speed exercise (Model RXT ATS required)
•Front-access mini USB connector for Kohler®SiteTech™ connection
•Integral Ethernet connector for Kohler®OnCue® Plus Generator Management System
•Built-in battery charger
•Remote two-wire start/stop capability for connection of Model RDT or other transfer switches
•Diagnostic messages
oDisplays diagnostic messages for the engine, generator, Model RXT transfer switch, programmable interface
module (PIM), and load management device
oOver 70 diagnostic messages can be displayed
•Maintenance reminders
•System settings
oSystem voltage, frequency, and phase
oVoltage adjustment
oMeasurement system, English or metric
•ATS status (Model RXT ATS required)
oSource availability
oATS position (normal/utility or emergency/generator)
oSource voltage and frequency
•ATS control (Model RXT ATS required)
oSource voltage and frequency settings
oEngine start time delay
oTransfer time delays
oVoltage calibration
oFixed pickup and dropout settings
•Programmable Interface Module (PIM) status displays
oInput status (active/inactive)
oOutput status (active/inactive)
•Load control menus
oLoad status
oTest function

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1.7 OnCue® Plus Generator Management System
The Kohler®OnCue®Plus Generator Management System is now included with the generator set. The OnCue®Plus System
allows monitoring and control of your generator set from your home or other location with Internet access using a computer or
mobile device. OnCue®Plus can be configured to send email or text message notifications in the event of a generator set fault.
You can also use Google Assistant or Amazon Alexa and your smart device to control your generator. Use voice commands to
check your generator’s status, check for active alerts, and start or stop an exercise. See the OnCue®Plus User Guide, TP-7006,
for simple setup instructions and voice commands.
OnCue®Plus Wireless is also available. OnCue®Plus Wireless works with the customer’s wireless Ethernet router and does not
require the installation of a network cable between the generator set and the customer’s router/modem.
1.8 Accessories
The following optional accessories are offered for the generator sets.
1.8.1 Cold Weather Package Kit
Heater kits are recommended for improved cold starting in locations where the ambient temperature drops below 0°C (32°F).
The cold weather package kit includes:
•Alternator brush cover
•Battery heater
•Breather tube heater
•Fuel regulator heater
•Oil heater
•Oil pressure sensor cover
•3-way extension cord for power connection
The heaters require a continuous source of AC power. See the generator set Installation Manual and the installation instructions
provided with the kits for more information.
1.8.2 Battery Heater Kit
The battery heater kit contains a heating wrap to help warm the battery in cold climates. See Figure 6. The battery heater is
equipped with a thermostat that turns the heater on at 16-18°C (60-65°F) and off at 27°C (80°F). Battery heaters are
recommended for regions where the temperature regularly falls below 0°C (32°F).
Note:
Battery heaters are compatible with all Kohler-supplied lead-acid batteries. For other battery types, check the battery
manufacturer’s instructions for any restrictions regarding the use of battery heaters.
The battery heater requires a source of AC power. Verify that AC power is connected to the generator set as described in the
generator set Installation Manual. The circuit must be backed up by the generator set to provide power at all times.