Operator Manual Transfer Switch RSS100 and RSS200 English 8-2007 962−0134 2008 Cummins Inc. All rights reserved.
Table of Contents SECTION TITLE PAGE SAFETY PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transfer Switch Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Safety Precautions This manual includes the following symbols to indicate potentially dangerous conditions. Read the manual carefully and know when these conditions exist. Then take the necessary steps to protect personnel and the equipment. the transfer switch must be performed only by a trained and experienced electrician or an authorized Cummins Onan service representative. If the cabinet must be opened for any reason: 1.
1. Introduction ABOUT THIS MANUAL TRANSFER SWITCH FUNCTION This manual covers transfer switch models produced under the Cummins® Power Generation brand name. This manual provides information necessary for operation of an RSS transfer switch with a control. Transfer switches are an essential part of a standby power system. The utility (normal power source) is backed up by a generator (emergency power source).
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2. Description Generator Power Connected − This amber LED is lit when the transfer switch is connected to the generator set which is supplying power to the load. This section describes how the basic components of a transfer switch function. TRANSFER SWITCH WITH CONTROL If this LED is flashing it means the transfer switch has failed to connect to or disconnect from the generator set, when commanded by the control. Figure 2-1 shows the operator panel used with transfer switches with a control.
TEST ACTIVITY LED GENERATOR POWER AVAILABLE LED PowerCommand UTILITY POWER AVAILABLE LED Test Control operation could be delayed by external source. Exercise Test Override Set Generator TEST PUSHBUTTON UTILITY POWER CONNECTED LED Exercise GENERATOR POWER CONNECTED LED SET EXERCISE PUSHBUTTON ACTIVE SET OR OVERRIDE PROGRAMMED PUSHBUTTON EXERCISE LED FIGURE 2-1. CABINET DOOR (SHOWN WITHOUT HINGED COVER) 2-2 2008 Cummins Inc. All rights reserved.
CONTROL TIME DELAYS Time Delay Normal to Emergency (TDNE) (Transfer) For transfer switches with an operator panel, the transfer switch control uses various time delays to break from one power source and connect to the other source. This time delay allows the generator set to stabilize before the load is applied. While connected to the utility, this time delay starts after utility power fails and the generator set becomes available (the amber Generator Power Available LED is lit).
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3. Operation PowerCommand Transfer Switch Test Control operation could be delayed by external source. Exercise Test Override Set Exercise FIGURE 3-1. CONTROL PANEL TRANSFER SWITCHES WITH AN OPERATOR PANEL SCREW TO BE REMOVED The transfer switch provides three operator pushbuttons and six LEDs that indicate operation status. PANEL COVER To access the operator panel, remove the screw securing the panel cover and open the cover (see Figure 3-2). FIGURE 3-2.
OVERRIDE To complete a system and periodic test, 1. Switch the main circuit breaker from the “ON” to the “OFF” position. The Override pushbutton is used to: S Terminate the following system time delays: 2. Make sure the following occurs. − Time Delay Engine Start (TDES) a. The generator control receives a signal to start the generator set. − Time Delay Normal to Emergency (TDNE) − Time Delay Emergency to Normal (TDEN) b.
GENERATOR EXERCISER 3. To start an immediate exercise period and have it repeat, press and hold the Set Exercise pushbutton for 5 seconds. The Exercise LED flashes at a rate of twice per second for 5 seconds and then stays on. Momentarily press the Set Exercise pushbutton a second time within ten seconds and an exercise period will start immediately. Momentarily pressing and releasing the Set Exercise pushbutton a second time starts an immediate 20 minute exercise period instead of waiting for 12 hours.
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4. Troubleshooting OPERATOR PANEL LED INDICATORS This section includes a description of the control LED indicators and provides preliminary troubleshooting checks. TEST ACTIVITY LED The operator panel contains six LED indicators that provide some information about the current control status and may be helpful in troubleshooting the transfer switch (see Figure 4-1). Descriptions of these indicators are included in Table 4-1.
TABLE 4-1. OPERATOR PANEL LED INDICATORS Definition Indicator Utility Power Available Utility Connected Generator Power Available Generator Connected Exercise This indicator lights when the utility source voltage sensor has determined that Utility power is available and is within acceptable voltage limits. 1. Lights constantly when the transfer switch is connected to the Utility. 2. Blinks once per second when the transfer switch has failed to connect to or disconnect from the Utility when commanded. 3.
TROUBLESHOOTING THE TRANSFER SWITCH switches that include a control panel. Common problems are listed with their possible causes. Refer to the corrective action column for the appropriate corrective procedure. Use the troubleshooting guide (Table 4-2) to help diagnose transfer switch problems with transfer TABLE 4-2. TROUBLESHOOTING TRANSFER SWITCHES WITH AN OPERATOR PANEL WARNING AC power within the cabinet presents a shock hazard that can cause severe personal injury or death.
TABLE 4-2. TROUBLESHOOTING TRANSFER SWITCHES WITH AN OPERATOR PANEL (CONTINUED) WARNING AC power within the cabinet presents a shock hazard that can cause severe personal injury or death. Do not remove the front panel under any circumstances. WARNING Improper operation of the generator presents a hazard that can cause severe personal injury or death. Observe all safety precautions in your generator manuals.
TABLE 4-2. TROUBLESHOOTING TRANSFER SWITCHES WITH AN OPERATOR PANEL (CONTINUED) WARNING AC power within the cabinet presents a shock hazard that can cause severe personal injury or death. Do not remove the front panel under any circumstances. WARNING Improper operation of the generator presents a hazard that can cause severe personal injury or death. Observe all safety precautions in your generator manuals. Problem The generator did not exercise when expected to. Possible Cause Corrective Action 1.
HOW TO OBTAIN SERVICE When the transfer switch requires servicing, contact your nearest Cummins Power Generation distributor. Factory-trained Parts and Service representatives are ready to handle all your service needs. Model No. ____________ To contact your local Cummins Power Generation (CPG) distributor in the United States or Canada, call 1-800-888-6626 (this automated service utilizes touch-tone phones only).
Cummins Power Generation 1400 73rd Ave. NE Minneapolis, MN 55432 USA Phone 1 763 574 5000 Toll-free 1 800 888 6626 Fax 1 763 574 5298 Email www.cumminsonan.com/contact www.cumminsonan.com CumminsR, OnanR, the “C” logo, and “Performance you rely on.” are trademarks of Cummins Inc. E2007 Cummins Power Generation, Inc. All rights reserved. 2008 Cummins Inc. All rights reserved.
