20
ABB Zenith
ZTSCT / ZBTSCT Operation & Maintenance Manual
Testing
(cont’d)
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 12).
• 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 genera-
tor 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.
Figure 12
Open Transition
Source 1 Power Failure:
When a Test is initiated, the controller initiates the initiates
the Time Delay Source 2 Start (Engine Start Timer “P”)
cycle. 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 stabilization before re-transfer. A
manual pushbutton BYPASS is provided to bypass the
“W” time delay if desired. After the (W) time delay, the
MX controller initiates a transfer signal through the
SCR-NO to operate the main transfer operator. The load is
now transferred to the Open position. The time delay to
Source 2 timer (DW) begins its timing cycle. After the
(DW) time delay, the MX controller initiates a transfer
signal through the SCR-E to operate the main transfer
operator. The load is now transferred to Source 2 line.
The transfer switch is mechanically locked. SN limit
switch awaits the next operation to Source 1.
Restoration of Source 1 Power:
Deactivating the Test switch initiates the re-transfer. When
Source 1 power reach the preset “Restore” values, the
controller initiates re-transfer to Source 1 sequence. The
delay to open Source 2 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 MX
controller initiates a transfer signal through the SCR-EO
to operate the main transfer operator. The load is now
transferred to the Open position. The time delay to
Source 1 timer (DT) begins its timing cycle. After the
(DT) time delay, the MX controller initiates a transfer
signal through the SCR-N to operate the main transfer
operator. The load is now transferred to Source 1 line.
The transfer switch is mechanically locked. SE limit
switch awaits the next operation to Source 2.
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.
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
A periodic test of the transfer switch under load conditions is recommended to insure proper operation.
(See National Electric Code articles 700 and 701)
NOTICE
