Operating the Liebert STS2 LED Display
Bypass Procedures for Source 2
To bypass the switch for Source 2:
NOTE
To bypass the Source 2 static transfer switch when Source 1 is presently active, you must first transfer to Source 2. See Manual Transfer / Preferred Source Selection on page 66.
1.Verify that Source 2 is supplying power via the LED display.
•If the LED Display is not available, check the gate driver board LEDs through the slots in the control panel. See Figure 47.
2.Remove the interlock key from CB4 and place it in the CB5 interlock.
3.Open the alternate source input breaker CB1. Verify that CB1 LED is off.
4.Rotate and remove the CB1 interlock key.
5.Insert the key in the CB5 bypass breaker interlock.
6.Rotate the interlock keys in the CB5 bypass breaker interlock to retract the interlock.
7.Close bypass breaker CB5. Verify that CB5 LED is on.
8.Open source input breaker CB2. Verify that CB2 LED is off.
9.Rotate the CB2 interlock key and remove it to lock out the breaker.
10.Secure the key according to your site’s lockout/tagout procedure.
11.Open output breakers CB3 and CB3A (if supplied) to remove power and isolate the static switch from the load.
Verify that CB3 and CB3A LEDs (if supplied) are off.
12.Verify that the output LED is on.
Power is now flowing directly from the source to the load, without passing through the static transfer switch.
To return to normal mode:
1.Verify that the LEDs for Source 2 are on, indicating that the source is supplying power and is operating within acceptable tolerances.
2.Insert the key in the CB2 breaker interlock.
3.Rotate the key to retract the interlock.
4.Close source input breaker CB2. Verify that CB2 LED is on.
5.Select the SOURCE 2 button in the SOURCE XFERS menu.
6.Close output breakers CB3 and CB3A (if supplied). Verify that CB3 and CB3A LEDs are on.
7.Verify that STS SOURCE 2 and OUTPUT LEDs are on.
8.Open bypass breaker CB5. Verify that CB5 LED is off.
9.Rotate the keys in the CB5 interlock to extend the interlock.
10.Remove the proper key from the CB5 interlock and insert it in the CB1 breaker interlock.
11.Rotate the key to retract the CB1 breaker interlock.
12.Close source input breaker CB1. Verify that CB1 LED is on.
