Transfer a Single UPS from Normal Mode to Maintenance Bypass Mode

Before performing this procedure, check the system status and that the bypass is working normally and is synchronized with the inverter.
  1. On the display, select and then select Function > To bypass.
  2. Remove the cover from the maintenance bypass breaker MBB. Refer to Location of Breakers - 400 V Systems.
    NOTE: When the cover of the MBB is removed, the system automatically transfers to maintenance bypass mode.
  3. Turn the maintenance bypass breaker MBB to the ON (closed) position.

    The load is now supplied via the maintenance bypass breaker.

  4. Turn the battery breaker(s) BB to the OFF (open) position.
  5. Turn the unit input breaker UIB to the OFF (open) position.
  6. Turn the static switch input breaker SSIB to the OFF (open) position.
  7. Turn the unit output breaker UOB to the OFF (open) position.
  8. For the UPS with internal batteries, disconnect all batteries on the front of the UPS.
    hazard of electrical shock, explosion or arc flash
    • Wait at least 5 minutes before removing the cover of the UPS after the display has turned off to allow for the capacitors to fully discharged.
    • Always measure for hazardous voltages on all terminals before working on the UPS.
    Failure to follow these instructions will result in death or serious injury.
  9. Do not reinstall the maintenance bypass breaker MBB cover. Leave the cover removed when the UPS is in Maintenance Bypass Mode.
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