990-5997B-001

Electrical Safety

DANGER
hazard of electric shock, explosion, or arc flash
  • Electrical equipment must be installed, operated, serviced, and maintained only by qualified personnel.
  • Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices.
  • Turn off all power supplying the UPS system before working on or inside the equipment.
  • Before working on the UPS system, check for hazardous voltage between all terminals including the protective earth.
  • The UPS contains an internal energy source. Hazardous voltage can be present even when disconnected from the mains supply. Before installing or servicing the UPS system, ensure that the units are OFF and that mains and batteries are disconnected. Wait five minutes before opening the UPS to allow the capacitors to discharge.
  • A disconnection device (e.g. disconnection circuit breaker or switch) must be installed to enable isolation of the system from upstream power sources in accordance with local regulations. The disconnection device must be easily accessible and visible.
  • The UPS must be properly earthed/grounded and due to a high leakage current, the earthing/grounding conductor must be connected first.
Failure to follow these instructions will result in death or serious injury.
DANGER
Hazard of electric shock, explosion, or arc flash
In systems where backfeed protection is not part of the standard design, an automatic isolation device (backfeed protection option or other device meeting the requirements of IEC/EN 62040–1 or UL1778 5th Edition – depending on which of the two standards apply to your local area) must be installed to prevent hazardous voltage or energy at the input terminals of the isolation device. The device must open within 15 seconds after the upstream power supply fails and must be rated according to the specifications.
Failure to follow these instructions will result in death or serious injury.

When the UPS input is connected through external isolators that, when opened, isolate the neutral or when the automatic backfeed isolation is provided external to the equipment or is connected to an IT power distribution system, a label must be fitted at the UPS input terminals, and on all primary power isolators installed remote from the UPS area and on external access points between such isolators and the UPS, by the user, displaying the following text (or equivalent in a language which is acceptable in the country in which the UPS system is installed):

DANGER
Hazard of electric shock, explosion, or arc flash
Risk of Voltage Backfeed. Before working on this circuit: Isolate the UPS and check for hazardous voltage between all terminals including the protective earth.
Failure to follow these instructions will result in death or serious injury.
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