Emerson Static Transfer Switch user manual Bypass Procedures for Source, To return to normal mode

Operating the Liebert STS2 LED Display

Bypass Procedures for Source 2

If transfer to Source 1 is not desired:

1.Follow the instructions to transfer the load to Source 2, if it is not the currently used source.

2.Remove the interlock key from CB4 and place it in CB5 interlock.

3.Open the alternate source input breaker CB1. The LED for CB1 is turned off.

4.Rotate and remove the interlock key.

5.Insert the key into the CB5 bypass breaker interlock and rotate the interlock keys in CB5 bypass breaker interlock to retract the interlock.

6.Close bypass breaker CB5. The LED for CB5 is turned on.

7.Open source input breaker CB2. The LED for CB2 is turned off.

8.Rotate the interlock key and remove it to lockout the breaker.

9.Open output breakers CB3 and CB3A (if supplied) to remove power from static switch. The LEDs for CB3 and CB3A (if supplied) turn off.

10.Verify that the output LED is lit.

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 key in the CB2 breaker interlock.

3.Rotate key to retract interlock.

4.Close source input breaker CB2. The LED for CB2 is turned on.

5.Close output breakers CB3 and CB3A (if supplied). The LEDs for CB3 and CB3A (if supplied) turn on.

6.Open bypass breaker CB5. The LED for CB5 is turned off.

7.Rotate keys in CB5 interlock to extend interlock.

8.Remove the proper key from CB5 interlock and insert it in CB1 breaker interlock.

9.Rotate key to retract CB1 breaker interlock.

10.Close source input breaker CB1. The LED for CB1 is turned on.

11.Verify that the output LED is lit.

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