Kohler RSB Intelligent Transfer Switch

Safety Precautions and Instructions

IMPORTANT SAFETY INSTRUCTIONS. Electromechanical equipment, including generator sets, 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 the presence of a hazard that will cause severe personal injury, death, or substantial property damage.

[WARNING] Warning indicates the presence of a hazard that can cause severe personal injury, death, or substantial property damage.

[CAUTION] Caution indicates the presence of a hazard that will or can cause minor personal injury or property damage.

[NOTICE] Notice communicates installation, operation, or maintenance information that is safety related but not hazard related.

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 connected equipment, disable the generator set as follows: (1) Move the generator set master switch to the OFF position. (2) Disconnect the power to the battery charger. (3) Remove the battery cables, negative (-) lead first. Reconnect the negative (-) lead last when reconnecting the battery. Follow these precautions to prevent starting of the generator set by an automatic transfer switch, remote start/stop switch, or engine start command from a remote computer.

Hazardous Voltage/ Moving Parts

[DANGER] Hazardous voltage. Will cause severe injury or death. Disconnect all power sources before opening the enclosure.

[DANGER] Hazardous voltage. Will cause severe injury or death. Only authorized personnel should open the enclosure.

[DANGER] Hazardous voltage. Will cause severe injury or death. This equipment must be installed and serviced by qualified electrical personnel.

Grounding electrical equipment. Hazardous voltage can 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, transfer switch, 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.

Short circuits. Hazardous voltage/current can 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.

Introduction

This manual provides operation instructions for the Kohler® Model RSB Intelligent Transfer Switch with MPACTM 550 electrical controls.

Information in this publication represents data available at the time of print. Kohler Co. reserves the right to change this literature 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 parts often and perform required service at the prescribed intervals. Obtain service from an authorized service distributor/dealer to keep equipment in top condition.

List of Related Materials

Separate manuals cover the installation of the Type 1 and Type 3R load centers and the transfer switch conversion kit. The following table lists the available manuals and part numbers.

Nameplate

A nameplate attached to the transfer switch includes a model designation, a serial number, ratings, and other information about the transfer switch. See Figure 3.

Check the transfer switch model number from the transfer switch nameplate and verify that it matches the model shown on the front cover of this manual before proceeding with installation.

Copy the model designation, serial number, and accessory information from the nameplate to the spaces provided in the Product Identification Information section located inside the front cover of this manual for use when requesting service or parts. Copy the model designation into the spaces in the Model Code chart and use the chart to interpret the model designation.

Figure 3 Typical Transfer Switch Nameplate: This figure shows a typical nameplate with numbered fields for Model Designation (1), Serial Number (2), and Factory-installed accessory numbers (3). It also displays manufacturer information, ratings, and a barcode.

Model Code

Record the transfer switch model designation in the boxes below. The transfer switch model designation defines characteristics and ratings as explained in the accompanying chart.

Figure: Model Code Structure: A diagram illustrating the components of a model designation: Enclosure, Main Breaker Current Rating, Generator Circuit Breaker Rating, Load Shed.

Kohler® Model Designation Key: This chart explains the Kohler® transfer switch model designation system. The sample model designation shown is for a Model RSB Intelligent Transfer Switch with MPACTM 550 electrical controls rated at 240 volts/60 Hz, 2 poles, 3 wires, and solid neutral in a type 1 enclosure with a 200 amp main circuit breaker, a 125 amp generator circuit breaker, and no load shed modules.

* Order a conversion kit for locations that already have a Square D® Generator-Ready Intelligent Load Center installed.

† Conversion kits are available without a main circuit breaker for installations that already include a type QOM main circuit breaker with control taps.

Note: Load centers do not include branch circuit breakers. Obtain Square D® type QO breakers locally as required for the application.

Service Assistance

For professional advice on generator set power requirements and conscientious service, please contact your nearest Kohler distributor or dealer.

• Consult the Yellow Pages under the heading Generators--Electric.
• Visit the Kohler Power Systems website at KohlerPower.com.
• Look at the labels and stickers 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.
• Outside the US and Canada, call the nearest regional office.

Regional Offices:

Headquarters Europe, Middle East, Africa (EMEA)

Kohler Power Systems
ZI Senia 122
12, rue des Hauts Flouviers
94517 Thiais Cedex
France
Phone: (33) 1 41 735500
Fax: (33) 1 41 735501

Asia Pacific

Power Systems Asia Pacific Regional Office
Singapore, Republic of Singapore
Phone: (65) 6264-6422
Fax: (65) 6264-6455

China

North China Regional Office, Beijing
Phone: (86) 10 6518 7950, (86) 10 6518 7951, (86) 10 6518 7952
Fax: (86) 10 6518 7955

East China Regional Office, Shanghai
Phone: (86) 21 6288 0500
Fax: (86) 21 6288 0550

India, Bangladesh, Sri Lanka

India Regional Office
Bangalore, India
Phone: (91) 80 3366208, (91) 80 3366231
Fax: (91) 80 3315972

Japan, Korea

North Asia Regional Office
Tokyo, Japan
Phone: (813) 3440-4515
Fax: (813) 3440-2727

Latin America

Latin America Regional Office
Lakeland, Florida, USA
Phone: (863) 619-7568
Fax: (863) 701-7131

Section 1: Description

1.1 Transfer Switch Description

An automatic transfer switch (ATS) transfers electrical loads from a normal source of electrical power to a standby source when the normal source voltage or frequency falls below an acceptable level. The normal source is typically utility power. The standby source is usually a generator set.

When the normal source fails, the ATS signals the standby source generator set to start. When the standby source reaches acceptable levels and stabilizes, the ATS transfers the electrical load to the standby source.

The ATS continuously monitors the normal source and transfers the load back when the normal source returns and stabilizes. After transferring the load back to the normal source, the ATS removes the generator start signal, allowing the generator set to shut down.

Figure 1-1 Typical ATS Block Diagram: This diagram illustrates a typical power system block. It shows inputs for Normal (Utility) Power and Standby (Generator) Power feeding into an Automatic Transfer Switch. The switch has a Transfer Mechanism and Electrical Controls. A signal to 'Start Generator' is shown, and the output is directed 'To Load'.

1.2 Intelligent Transfer Switch

The Model RSB Intelligent Transfer Switch is intended for use in an optional standby power system to allow a homeowner to switch between utility and generator power by means of an integrated automatic transfer mechanism.

The MPACTM 550 controller monitors utility power for interruptions. When utility power is lost, the controller signals the generator set to start. The transfer mechanism switches pre-determined electrical components to the generator.

When utility power is restored, the MPACTM 550 controller commands the transfer mechanism to switch the electrical load back to the utility and shuts down the generator set.

The Intelligent Transfer Switch is available in two enclosures, accommodating up to 40 (Type 1) or 28 (Type 3R) branch circuits selected by the user for backup power. It is suitable for service entrance or sub-panel use.

FCC Statement

This transfer equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This transfer equipment generates and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation.

If this transfer equipment does cause harmful interference to radio or television reception, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.
• Increase the separation between the transfer equipment and the receiver.
• Connect the receiver into an outlet on a different circuit.
• Consult the receiver dealer or an experienced radio/TV technician for help.
• Do not make changes or modifications to the transfer equipment that are not expressly approved by Kohler Co. Any changes or modifications may result in the loss of authority to operate the equipment.

1.3 Specifications

Figure 1-2 Weights and Dimensions

Figure 1-3 Specifications

Section 2: Operation

2.1 Introduction

Red and green LEDs on the transfer switch controls indicate which sources are available, show which source is connected to the load, and flash to indicate fault conditions. Pushbuttons allow you to start and stop the generator set (with or without transferring the load) and set the exercise timer. See Figure 2-1.

The transfer switch uses factory-default settings for time delays, voltage and frequency pickup and dropout, and other system settings. An optional accessory board allows changes to the time delays and exerciser settings and provides connections for remote test and remote exercise inputs. See Section 4.1 for information on the accessory board.

2.2 Pushbuttons and Indicators

Figure 2-1 User Interface Panel: This figure identifies the controller pushbuttons and LED indicators. It shows the location of the Utility Source Available LED, Utility Source Position LED, Test Button, Generator Source Available LED (labeled GEN), Generator Position LED, and Exercise Button.

The LEDs light steadily or flash to indicate different ATS conditions as shown in Figure 2-2. See Section 2.5 for more information on fault conditions.

Figure 2-2 LED Indication

2.3 Source Sensing

The transfer switch controller monitors the utility power source voltage and initiates the transfer sequence if the source voltage falls below the voltage dropout setting. Retransfer is initiated when the utility source rises above the voltage pickup settings and remains stable for at least 6 minutes. See Figure 2-3.

Figure 2-3 Source Sensing

2.4 Sequence of Operation

Figure 2-4 illustrates the transfer sequence when the normal source fails and Figure 2-5 illustrates the sequence when it returns. Time delays before load transfer prevent nuisance transfers during brief power interruptions.

Total transfer time depends on the generator set engine cranking time and other factors. Events such as the failure of the generator set to start can change the sequence of operation.

If the standby source fails and the normal source is not available, the transfer switch controller powers down until one of the sources returns.

Transfer will not occur if one of the source circuit breakers opens on a fault.

The time delay option board allows time delay adjustments. See Section 4.1.

Figure 2-4 ATS Sequence of Operation, Transfer to Standby: This flowchart shows the sequence when normal power source voltage falls below 80% of nominal. It includes steps like Undervoltage dropout time delay, Load control contact opens, Engine start time delay, Generator set engine crank and start, Transfer time delay, Load shed circuit breakers open, and Command to transfer to the standby source. An asterisk indicates that the time delay option board allows adjustment.

Figure 2-5 ATS Sequence of Operation, Retransfer to Normal: This flowchart shows the sequence when normal power source voltage rises above 85% of nominal. It includes steps like Retransfer from standby to normal time delay, Command to transfer to the normal source, Load control contact closes, Load shed circuit breakers close, Time delay engine cooldown, and Engine start signal removed. An asterisk indicates that the time delay option board allows adjustment.

2.4.1 Time Delays

The controller time delays are shown in Figure 2-6. For adjustable time delays, install the accessory board. See Section 4.1.

The Failure to Acquire Standby Time Delay is set for 78 seconds to match the crank cycle of the Kohler generator set controller.

The fault clears when the system acquires the standby source.

Figure 2-6 Time Delays

* Allows for three 15 sec. engine starting attempts separated by 15 sec. rest periods.

2.4.2 Load Control

The load control contact is closed when the transfer switch is in the Normal position. The contact opens when the Normal source is lost to allow disconnection of a load. The load connected to the load control contact is not powered by the standby source. The load control step in the sequence of operation is shown in Figure 2-4.

2.4.3 Load Shed

The optional load shed kit allows disconnection of selected loads before transfer to the generator set. Remote-controlled circuit breakers connected to the optional load shed module(s) open before transfer to the generator set. After transfer back to the utility source, the remote-controlled circuit breakers close.

2.5 Faults

The LEDs on the controller's user interface flash as shown in Figure 2-2 to indicate various fault conditions. Contact an authorized distributor/dealer for service if the fault persists.

2.5.1 Failure to Acquire Standby Source Warning

The Failure to Acquire Standby Source fault occurs if the transfer switch does not sense voltage from the generator set within 78 seconds after signalling the generator set to start. Check the generator set operation and the connections from the generator set to the ATS in the case of this fault.

2.5.2 Failure to Transfer Warning

The Failure to Transfer warning occurs if a signal to transfer is sent to the contactor and the position-indicating contacts do not indicate a complete transfer.

The controller will attempt to transfer three times before indicating the fault. If the transfer switch is in the Normal position, the Engine Cooldown time delay is executed and then the engine start contacts open to stop the generator set.

Reset the controller to clear the fault condition. See Section 2.6.

2.5.3 Auxiliary Switch Fault

An Auxiliary Switch fault occurs if the controller is unable to determine the transfer switch position. If the transfer switch is in the Normal position, the Engine Cooldown time delay is executed and then the engine start contacts open to stop the generator set.

Reset the controller to clear the fault condition. See Section 2.6.

2.6 Controller Reset

2.6.1 Fault Reset

Always identify and correct the cause of a fault condition before clearing the faults from the ATS controller. Press and hold the Exercise and Test buttons for approximately 3 seconds until the LEDs flash to clear all faults and warnings. Warnings reset automatically with a change in the source availability or a signal to transfer.

2.6.2 Alarm Silence

If the transfer switch is equipped with a time delay option board, pressing both buttons for 3 seconds will also silence the alarm horn.

2.6.3 Controller Reset

Press and hold both buttons for 6 seconds to reset the controller to its original state at powerup.

2.7 Running a Test

Follow the instructions below to start and stop a loaded or unloaded test. Once started, a test sequence will continue to run until ended by the operator as described in the procedures below.

If the standby source fails during a test run and the normal source is available, the load is transferred back to the Normal source and the test function is deactivated. The standby source available LED stops flashing when the standby source is no longer available. See Figure 2-1 for the location of the Test button.

2.7.1 Unloaded Test

During an unloaded test, the generator set starts and runs, but the electrical load is not transferred to the standby source.

To start an unloaded test:

• Press and hold the Test button for 3 seconds. The standby source available LED flashes.
• After the engine start time delay, the generator set starts. (The load is not transferred.)
• The Generator Available LED flashes at 1 Hz.

To end the test:

• Press and hold the test button for 2 seconds.
• The generator set stops.
• The Generator Available LED stops flashing when the standby source is no longer available.

2.7.2 Loaded Test

During a loaded test, the generator set starts and runs. The ATS transfers the electrical load from the normal source to the standby source. At the signal to end the test, the ATS transfers the load back to the normal source before signalling the generator set to stop.

Note: If the optional load shed kit is installed, the loads connected to the remote-controlled circuit breakers will be turned off during a loaded test.

To start a loaded test:

• Press and hold the Test button for 6 seconds, until the standby source available and standby position LEDs flash.
• After the engine start time delay, the generator starts. The Generator Available LED flashes at 1 Hz.
• The load control contact opens.
• The optional load shed circuit breakers open.
• After the normal-to-standby time delay, the ATS transfers the load to the standby source.

To end the test:

• Press and hold the test button for 2 seconds.
• After the standby-to-normal time delay, the ATS transfers the load back to the normal source.
• The load control contact closes.
• The optional load shed circuit breakers close.
• After the engine cooldown time delay, the generator set stops.
• The Generator Available LED stops flashing when the standby source is no longer available.

2.8 Exerciser

Follow the instructions below to set the exercise timer to automatically start and run the generator set for 20 minutes every week. The exerciser can be set for loaded or unloaded exercise runs. The factory settings for the exerciser are summarized in Figure 2-7.

Figure 2-7 Exerciser Settings

* The time delay option board allows adjustment of these parameters.

The time delay option board allows setting the exerciser for biweekly exercise runs and adjustment of the exercise run duration from 5 to 50 minutes. See Section 4.1.

2.8.1 Unloaded Exercise

During an unloaded exercise, the generator set runs but the electrical load is not transferred from the normal source to the generator set.

Press and hold the Exercise button for approximately 3 seconds to start an unloaded exercise and set the time and date of the next exercise run.

To start an unloaded exercise AND set the exercise timer:

On the day and time that you want the exercise to run every week (for example, at 1 p.m. every Tuesday):

• Press and hold the Exercise button for 3-5 seconds, until the GEN Available LED flashes.
• The generator set starts.
• The GEN available LED continues to flash throughout the exercise run to indicate an unloaded exercise.
• After approximately 20 minutes, the ATS signals the generator set to stop.

The timer is now set to run an unloaded exercise at the same time and day every week.

2.8.2 Loaded Exercise

During a loaded exercise, the generator set runs and the ATS transfers the electrical load to the generator set.

Note: If the optional load shed kit is installed, the loads connected to the remote-controlled circuit breakers will be turned off during a loaded exercise.

To start a loaded exercise AND set the exercise timer:

On the day and time that you want the exercise to run every week (for example, at 1 p.m. every Tuesday):

• Press and hold the Exercise button for at least 6 seconds, until both the GEN available and GEN position LEDs flash.
• The generator set starts.
• The optional load shed circuit breakers open.
• The ATS transfers the load to generator set.
• The GEN available and GEN position LEDs continue to flash throughout the exercise run to indicate a loaded exercise.
• After approximately 20 minutes, the ATS transfers the load back to the normal source.
• The optional load shed circuit breakers close.
• The ATS signals the generator set to stop.

The timer is now set to run a loaded exercise at the same time and day every week.

If the standby source fails during an exercise run and the normal source is available, the load is transferred back to the Normal source. The standby source available LED stops flashing, and the Failure to Acquire Standby Source alarm is activated.

2.8.3 Stopping Exercise Run

If it is necessary to stop the generator set during an exercise run, press and hold the exercise button for 2 seconds. Ending the current exercise period early does not affect future exercise runs.

2.8.4 Resetting Exerciser

To set a new exercise time and day, just follow the instructions for setting the exerciser, above. The exerciser will then be reset for the new time and day.

To clear the exerciser setting, press and hold the Exercise and Test buttons for at least 6 seconds.

Section 3: Scheduled Maintenance

3.1 Introduction

Regular preventive maintenance ensures safe and reliable operation and extends the life of the transfer switch. Preventive maintenance includes periodic testing, cleaning, inspection, and replacement of worn or missing components. Section 3.4 contains a service schedule for recommended maintenance tasks.

A local authorized distributor/dealer can provide complete preventive maintenance and service to keep the transfer switch in top condition. Unless otherwise specified, have maintenance or service performed by an authorized distributor/dealer in accordance with all applicable codes and standards. See the Service Assistance section in this manual for how to locate a local distributor/dealer.

Keep records of all maintenance or service.

Replace all barriers and close and lock the enclosure door after maintenance or service and before reapplying power.

3.2 Testing

3.2.1 Weekly Generator Set Exercise

Use the exerciser or a manual test to start and run the generator set under load once a week to maximize the reliability of the standby power system. See Section 2.7 for test instructions and Section 2.8 for instructions to set the exerciser.

Optional accessories allow adjustment of the exercise schedule and duration. See Sections 2.8 and NO TAG. Refer to the generator set operation manual for exercise recommendations.

3.2.2 Monthly Automatic Control System Test

Test the transfer switch's automatic control system monthly. See Section 2.7 for the test procedure.

• Verify that the expected sequence of operations occurs as the switch transfers the load to the standby source when a preferred source failure occurs or is simulated.
• Observe the indicator LEDs included on the transfer switch to check their operation.
• Watch and listen for signs of excessive noise or vibration during operation.
• After the switch transfers the load to the standby source, end the test and verify that the expected sequence of operations occurs as the transfer switch retransfers to the preferred source and signals the generator set to shut down after a cooldown period.

3.3 Inspection and Service

Contact an authorized distributor/dealer to inspect and service the transfer switch annually and also when any wear, damage, deterioration, or malfunction of the transfer switch or its components is evident or suspected.

3.3.1 General Inspection

External Inspection. Keep the transfer switch clean and in good condition by performing a weekly general external inspection of the transfer switch for any condition of vibration, leakage, excessive temperature, contamination, or deterioration. Remove accumulations of dirt, dust, and other contaminants from the transfer switch's external components or enclosure with a vacuum cleaner or by wiping with a dry cloth or brush.

Note: Do not use compressed air to clean the transfer switch because it can cause debris to lodge in the components and damage the switch.

Tighten loose external hardware. Replace any worn, missing, or broken external components with manufacturer-recommended replacement parts. Contact a local authorized distributor/dealer for specific part information and ordering.

3.3.2 Other Inspections and Service

Have an authorized distributor/dealer perform periodic inspections, scheduled maintenance, and service to ensure the safe and reliable operation of the transfer switch. See Section 3.4, Service Schedule, for the recommended maintenance items and service intervals.

Have an authorized distributor/dealer repair or replace damaged or worn internal components with manufacturer-recommended replacement parts.

3.4 Service Schedule

Follow the service schedule below for the recommended service intervals. Activities designated by an X may be performed by the switch operator. Have all other maintenance and service performed by an authorized distributor/dealer.

* Service more frequently if the transfer switch is operated in dusty or dirty areas.

See Section: Read these sections carefully for additional information before attempting maintenance or service.

Visually Inspect: Examine these items visually.

Check: Requires physical contact with or movement of system components, or the use of nonvisual indications.

Adjust, Repair, Replace: Includes tightening hardware. May require replacement of components depending upon the severity of the problem.

Clean: Remove accumulations of dirt and contaminants from external transfer switch's components or enclosure with a vacuum cleaner or by wiping with a dry cloth or brush. Do not use compressed air to clean the switch because it can cause debris to lodge in the components and cause damage.

Test: May require tools, equipment, or training available only through an authorized distributor/dealer.

Symbols used in the chart: X=The transfer switch operator can perform these tasks. D=An authorized distributor/dealer must perform these tasks. W=Weekly M=Monthly Q=Quarterly S=Semiannually (every six months) Y=Yearly (annually)

Section 4: Accessories

4.1 Accessory Board

[DANGER] Hazardous voltage. Will cause severe injury or death. Disconnect all power sources before opening the enclosure.

The optional accessory board is mounted with standoffs on the controller's main logic board. See Figure 4-1 for the accessory board location and components.

The accessory board contains the following components:

• Audible alarm to indicate system faults.
• Rotary switches for time delay adjustments.
• DIP switches for exercise, remote test switch operation, and load control functions.
• Connectors for remote test input and generator set supplying load output.

4.1.1 Accessory Board Audible Alarm

The audible alarm sounds on the fault conditions shown in Section 2.5.

Alarm Silence/Fault Reset. Press and hold the test and exercise pushbuttons on the controller to silence the alarm and reset the fault. Always identify and correct the cause of the fault condition before resetting the controller.

Figure 4-1 Accessory Board Location and Components: This figure shows the physical layout of the accessory board and its components. It labels: 1. MPAC 550 controller circuit board, 2. Accessory board, 3. 4-pin connector, 4. Engine cooldown time delay adjust SW1, 5. Engine start time delay adjust SW2, 6. Normal to standby time delay adjust SW3, 7. Standby to normal time delay adjust SW4, 8. Exercise run time adjust SW5, 9. DIP switches SW6, 10. Input/output connector P9 (black).

4.1.2 Accessory Board Time Delay Adjustment Switches

The 10-position rotary switches allow adjustment of the time delays shown in Figure 4-2. Use a small screwdriver or other small tool to increase or decrease the time delays within the range shown in the table. The rotary switch positions range from 1 to 10, with position 10 labeled 0 (zero).

The factory settings are the same as the controller time delays without the optional accessory board.

Figure 4-2 Accessory Time Delay Adjustment Switches

4.1.3 Accessory Board DIP Switches

DIP switches on the optional accessory board control the exercise, remote test, and load control functions. The DIP switch location is shown in Figure 4-1. The DIP switch functions are summarized in Figure 4-3. Check the DIP switch settings and adjust if necessary for the application.

1 Week/2 Week Exercise, Switch 1. This switch controls the time interval for exercise runs that are set by pressing the Exercise button on the ATS controller. If the setting is changed after the exerciser has been set, the new schedule becomes effective after the next exercise.

Switch 2. This switch is not used.

Maintained/Momentary Test, Switch 3. Set this switch for a maintained or momentary remote test (start/stop) switch, as follows:

• ON (maintained) position: close a remote test switch or contact to start and run the generator set. Open the remote contact to end the test and signal the generator set to stop.
• OFF (momentary) position: hold the remote test switch closed for 1 second and release to start a test. The remote switch must be held closed for at least 1 second. Operate the test switch again to stop the test and signal the generator set to stop.

Note: The generator set continues to run during the engine cooldown time period after receiving the remote stop signal. See Figure 4-2 for time delays.

Switch 4. This switch is not used.

Alarm Enable, Switch 5. Enables or disables the alarm horn on the accessory board. If the alarm is disabled, the horn will not sound.

Install the enclosure cover before energizing the transfer switch.

Figure 4-3 Accessory Board DIP Switches

4.2 Load Shed Kit

The optional load shed kit disconnects selected loads before transfer to the emergency source, reducing the load on the generator set. See Section 2 for descriptions of the load shed operation during normal operation, test and exercise.

Transfer switches that are factory-equipped with the load shed accessory have a letter S at the end of the model designation. See the model code chart in the Introduction.

The load shed kit includes one or two load shed modules which connect to remote-controlled branch circuit breakers (sold separately). Type 1 enclosures can have one or two load shed modules installed. Type 3R enclosures can have one load shed module installed. Up to 6 one- or two-pole circuit breakers can connect to each module. See Figure 4-4 and Figure 4-5 for the load shed module location.

Figure 4-4 Type 1 Enclosure with Two Load Shed Modules: This figure shows a Type 1 enclosure with two load shed modules. It labels '1. Circuit breaker interface modules'.

Figure 4-5 Type 3R Enclosure with One Load Shed Module: This figure shows a Type 3R enclosure with one load shed module. It labels '1. Circuit breaker interface module'.

Appendix A: Abbreviations

The following list contains abbreviations that may appear in this publication.