GE Entelli-Switch 250 manual Testing cont’d, ATS Testing, Standard Transition, Delayed Transition

Testing (cont’d)

NOTICE

A periodic test of the transfer switch under load conditions is recommended to insure proper operation.

(See National Electric Code articles 700 and 701)

ATS Testing

Start generator and verify proper voltage, frequency and phase sequence (match to Source 1). Shut down gen set and place in Auto. Complete the visual inspection of the transfer switch, and close the cabinet door.

Initiate the test by pressing the TEST button on the LCD keypad. The controller will then prompt for your access code. After entering the code, three test options will appear— XFR LOAD, FAST TEST and NO XFR (See Figure 11).

•XFR LOAD test starts the generator and using the current timer settings, transfers the load to Source 2.

•FAST TEST test presets timer values to a maximum 30 seconds during the test. After completion of the test, all timers are reset to their original values. (T3, W3, DT and DW remain)

•NO XFR test starts the generator but does not transfer the load to the Source 2.

Press and hold the desired test option button until the switch transfers to Source 2 (load test) or until the generator has been run for the desired amount of time (no load test). Releasing the test button before W timer timeout will abort the test (Exception: when the transfer commit option, is configured “ON”).

To test lamps, press TEST then scroll through MORE, then press LAMP TEST. To cancel LAMP TEST press MORE.

Standard Transition

When the test is initiated, the controller initiates the Time Delay Source 2 Start Timer (Engine Start Timer "P") cycle. A manual CANCEL button is provided to cancel the test if desired. Upon completion of the (P) time delay, an Engine start Signal is sent to Source 2. When Source 2 voltage and frequency reach the preset "Restore" Values, the time delay to Source 2 Timer (W) begins its timing cycle to ensure voltage and frequency stabilization before transfer. A manual pushbutton BYPASS is provided to bypass the "W" time delay if desired. After the (W) time delay, the CCE relay energizes the CE solenoid to close the transfer switch in to Source 2. The SE limit switch activates to de-energize the CCE relay.

Restoration of Source 1 Power:

Deactivating the test switch initiates re-transfer to Source 1 sequence.The delay to Source 1 Timer (T) begins its timing cycle to ensure voltage and frequency stabilization before retransfer.

A manual pushbutton BYPASS is provided to bypass the "T" time delay if desired. After the (T) time delay, the CCN relay energizes the CN solenoid to retransfer the switch to Source 1. The SN limit switch activates to de-energize the CCN relay.

Immediately after re-transfer, the S2 Stop Delay Timer (Delay to Engine Stop "U") begins its cycle to allow Source 2 Engine

S Y S T E M T E S T

FA S T X F R N O

M O R E T E S T L O A D X F R

Figure 11

to run unloaded. A manual pushbutton BYPASS is provided to bypass the "U" time delay if desired. Upon completion of the

(U) timing cycle, the controller sends an Engine stop signal.

Delayed Transition

Source 1 Power Failure:

When the test is initiated, the controller initiates the Time Delay Source 2 Start (Engine Start Timer "P") cycle. A manual CANCEL button is provided to cancel the test if desired Upon completion of the (P) time delay, an Engine start Signal is sent to Source 2. When Source 2 voltage and frequency reach the preset "Restore" values, the time delay to open Source 1 timer

(W)begins its timing cycle to ensure voltage and frequency sta- bilization before re-transfer. A manual pushbutton BYPASS is provided to bypass the "W" time delay if desired. After the (W) time delay, the CCNO relay energizes the CNO solenoid to open the transfer switch out of Source 1 position. The time delay to Source 2 timer (DW) begins its timing cycle. After the (DW) time delay, the CCE relay energizes. The switch then completes transfer to Source 2 by energizing the CE solenoid. The SE limit switch activates to de-energize the CCE relay.

Restoration of Source 1 Power:

Deactivating the test switch initiates re-transfer to Source 1sequence.The delay to open Source 2 Timer (T) begins its tim- ing cycle to ensure voltage and frequency stabilization before retransfer. A manual pushbutton BYPASS is provided to bypass the "T" time delay if desired. After the (T) time delay, the CCEO relay energizes the CEO solenoid to open the switch out of Source 2 position. The time delay to Source 1 timer (DT) begins its timing cycle. After the (DT) time delay, the CCN relay energizes the CN solenoid to complete re-transfer of the switch to Source 1. The SN limit switch activates to de-energize the CCN relay.

Immediately after re-transfer, the S2 Stop Delay Timer (Delay to Engine Stop "U") begins its cycle to allow Source 2 Engine to run unloaded. A manual pushbutton BYPASS is provided to bypass the "U" time delay if desired. Upon completion of the

(U) timing cycle, the controller sends an Engine stop signal.

■ GE Zenith Controls Entelli-Switch 250 Operation and Maintenance Manual (71R-2000) 21 ■