Can you switch-on an UPS when the Main Supply is Off?

Can you switch-on an UPS when the Main Supply is Off?

Please anyone give me the correct answer

Yes, you can turn on a UPS when the main power is turned off, although this depends on the type of UPS & the battery condition:

  • Offline (or) Standby UPS
  • Online or Double-Conversion UPS

Offline (or) Standby UPS

Normally turns off until the mains fails.

Can turn on from batteries, only if:

  • The battery is fully charged.
  • The UPS includes a cold start option (manual startup without mains power).

Online or Double-Conversion UPS

  • Uses an inverter to operate even when connected to the mains.
  • If the cold start capability is present, the vehicle can be started directly from the battery.

Important Condition

  • The battery must be sufficiently charged to support the load.
  • The Cold Start Feature is required to turn on the UPS without a mains supply.
  • Not all UPS models offer cold start; consult the user handbook or specifications.

Yes, you can use a UPS without a mains supply if it enables cold start & the battery is in good condition.

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