Liebert Series 600T manual B2. Set the Static Switch Disconnects OFF open

NOTE

If the system was shut down in response to an “Emergency Off, there may be alarm messages on the LCD screen that describe system conditions before (or at the time of) the shutdown. Some or all of the alarm conditions may have already been resolved. To clear these alarm messages, turn off the control power (see Figure 8 and Figure 9). Wait at least ten minutes for the control power circuitry to completely de- energize. After ten minutes, turn control power back on and wait two minutes before continuing.

CAUTION

If you are recovering from a UPS system shutdown for maintenance procedures, verify that all of the SCC doors are closed and latched. All test equipment must be removed from the system. All electrical connections must be secure.

Power must be provided to the UPS controls so the operator can use the LCD display and so the system logic can perform its control functions. Note that you can use the LCD display to monitor UPS system status, even when the UPS modules are not operating.

During a start-up procedure, power is supplied to the critical load through the UPS (internal) bypass line while the UPS modules are being energized. Depending on the reason for your UPS system shutdown, you may already have power through the bypass line. You can determine this by observing the Monitor/Mimic Display screen at the System Control Cabinet (SCC).

Step 2. If the bypass line is not supplying the load, the LCD screen will be blank. Energize the bypass line by operating the following controls:

a.Close the Bypass Input Breaker (BIB). This breaker may be in your Maintenance Bypass cabinet.

NOTE

Wait two minutes after applying bypass power before you operate any other UPS controls.

CAUTION

DO NOT assume that the UPS System Bypass Breaker (SBB) is closed.

Instructions for operating the Maintenance Bypass circuit breakers are on the Maintenance Bypass cabinet.

Make sure you understand the proper sequence before operating any circuit breaker. Operating a Maintenance Bypass circuit breaker out of sequence could cut off power to the critical load.

b.Observe the Monitor/Mimic Display screen to determine if your System Bypass circuit breaker (SBB) is closed and whether the UPS Bypass line is supplying power to the critical load.

If your System Bypass circuit breaker is open (as in recovering from an Emergency Power Off or Low Battery Shutdown), close this circuit breaker as follows:

b1. Open the SCC control panel door and find the Transfer Relay Board (Figure 11). If the red LED (CR18) labeled TOT S/D (Total Shutdown) is on, press the Bypass Reset switch (SW1) on this board. The red LED should turn off.

b2. Set the Static Switch Disconnects (Figure 9) OFF (open).

NOTE

Depending on SCC model, the static switch disconnects can be two circuit breakers, contactors or plug-in connections on a drawout carriage assembly. The location could be at the front, right, or rear of the cabinet. Refer to the drawing of the SCC cabinet selected for your UPS system.

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