66 30-200 kW P-164000249User's and Installation Guide Revision 26.4.7 UPS system and critical load shutdownTo perform maintenance or service on the critical load, shut down power to the load by performingthe following procedure:1. Turn off all equipment that is being powered by the UPS system.2. Perform the LOAD OFF procedure (see Chapter 6.4.8 De-energizing the Critical Load onpage 66). The input, output, and bypass backfeed contactors open, the battery breaker ordisconnect is tripped, and the power module is turned off.DANGERPower is present inside the UPS cabinet until the upstream input feeder circuit breaker isopened.3. Unfasten the front door latch and swing the door open.4. Open the rectifier input switches if included in the UPS system, and verify that battery breakeris open, and close the front door.5. Open the UPS input and bypass feeder circuit breakers.6. Repeat steps 3-5 for all UPSs in the system.6.4.8 De-energizing the Critical LoadA UPS system Load Off is initiated by the Load Off button from Controls > System Controls screen. Thisbutton can be pressed to control the UPS output. The Load Off button de-energizes the critical load andpowers down the UPS system.The UPS system (including Bypass) remains off until restarted.1. Press Load Off.The shut down screen appears, providing a choice to proceed or abort the shutdown.NOTEAll power to the critical load is lost when Load Off is selected in the following step. Youshould use this feature only when you want to de-energize the critical load.2. To shut down the UPS, press Load Off. To abort the shutdown, press ABORT. When Load Offis selected, the input, output, and bypass backfeed contactors open, the battery breaker ordisconnect is tripped, and all the UPSs in the system are turned off.DANGERDo not attempt to restart the system after Load Off until the cause of the shutdown hasbeen identified and cleared.
