Testing 
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 
SYSTEM TEST 
FAST XFR   NO 
MORE TEST LOAD XFR 
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 
ZTS / ZTSD Operation and Maintenance Manual (71R-3000) 
19