Generator

[hhsting]

I have ambulatory center outpatient with two sources of power one utility the other generator. The generator side has three ATS with three branches: life safety branch, equipment branch, and critical branch. The question is the generator type would it be called standby, emergency or legally required generator?

 

[GoldDigger]

Since it serves three different branch types, it must meet the minimum requirements of all three. Call it by the most restrictive purpose and make sure that lower priority branches cannot compromise the life safety branch in case of a fault or overload.

 

[hhsting]

Which branch has most priority and turns on by the generator first critical, life and safety or equipment branch?

 

[charlie b]

Per 517.32(B), both the life safety and the critical branch must be energized within 10 seconds of the loss of utility power. Per 517.35, the equipment branch loads may be reenergized with appropriate delays. But to answer your first question, I always, and I do mean always, use the word "backup" to describe any generator. The notion of whether it supplies emergency or other loads comes into a separate sentence.

 

[Hv&Lv]

Per 517.32(B), both the life safety and the critical branch must be energized within 10 seconds of the loss of utility power. Per 517.35, the equipment branch loads may be reenergized with appropriate delays. But to answer your first question, I always, and I do mean always, use the word "backup" to describe any generator. The notion of whether it supplies emergency or other loads comes into a separate sentence.

Did not know it was 10 seconds... learn something new every day.

Question. You ever run into problems with the generator startup timing with station and/or recloser operations? I’ve seen some as long as a 10 second third shot.
Just let the generator come on and run at the first blink? Second one?

 

[roger]

Did not know it was 10 seconds... learn something new every day.

Question. You ever run into problems with the generator startup timing with station and/or recloser operations? I’ve seen some as long as a 10 second third shot.
Just let the generator come on and run at the first blink? Second one?

Anything more than a blip, and then there's a delay returning to normal power and in my experience it is usually a few minutes, it wants to be sure that the normal source is back on for the long run.

Roger