UPS protection

[mady]

Dear sirs,

As you are aware,UPS unit is provided with two protective devices (built-in), one on the inverter circuit and the second on the bypass.
Please advise if there is a code requirement to provide another external protection for the UPS.

Thank you,

Mady

 

[mc5w]

Re: UPS protection

If you have a roomful of computers you would need to have an emergency stop button(s) at the exit(s) that will shut down the UPSs. There is also a requirement for emergency stopping of ventilation for a computer room.

 

[ron]

Re: UPS protection

Mady,
The protection offered at the input to the inverter will not offer great protection for the output feeders. A breaker on the output will give more accurate protection, as the one on the input sees the losses of the UPS in addition to the load.

As a side note, MC5W, the requirements for an EPO and HVAC shutdown are not required by the NEC if the installation will comply with the first 4 chapters of the NEC.