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Question concerning Phase drop.

Question concerning Phase drop.

Question concerning Phase drop.

(OP)
Not too long ago we had power feed problems to the facility that I'm presently managing.  After power was restored we noticed almost half of the fluorescent bulbs in the gymnasium did not come back on and we found they were burnt out.  My question is could the dropped phase be the cause of this damage? We had to change out over 800 fluorescent lamps afterward.   
Thanks for any info

Tom....

RE: Question concerning Phase drop.

It depends.  Can you more thoroughly describe the system and what the "problems" were?

RE: Question concerning Phase drop.

(OP)
Sorry bout that..
This is a large Physical Fitness Center on a government installation.
We have three phase feed to the facility and we lost one phase.
The facility was supposed to have phase protection but apparently it didn't work.  It wreaked havoc on our pump motors, a digital pool chemical controller and about half of the fluorescent bulbs in the gymnasium.
The lights are six to a fixture and we have 268 light fixtures in the gym they are on a relay system using Proline T8  #GE232-10V -N 120 -277 Volts 50-60 Hz Ballasts
There were very few lamps burnt out prior to us dropping a phase, but afterward almost half the lamps were burnt up..

Could this have been a result of the phase drop?

Thanks for any reply..

RE: Question concerning Phase drop.

There are certainly ways to make this happen but you're not giving us any info to work with.

Hard to tell since you haven't described what exactly,

Quote:

power feed problems to the facility
, consisted of.

You also haven't told us which way those ballasts are wired, 277V or 120V?

Keith Cress
kcress - http://www.flaminsystems.com

RE: Question concerning Phase drop.

In addition of dropped phase, it sure appeared some other phenomenon that affected power quality and produced all those damages

If there was no electricity there would be no internet. Good point, don´t you? :D

RE: Question concerning Phase drop.

TomFitz, where exactly did the 'phase drop' occur in the system? If it was on the primary side of a transformer, what type of transformer is it (voltage, wye, delta, etc.)? What is the feed to the transformer like (overhead, underground)? How far back up the system was the phase disconneced. What else is connected to the primary side between the open point and your transformer?

I'm not familiar with the GE ballast you mentioned and its possible failure modes. Its difficult to believe that a modern electronic ballast would damage a lamp due to low voltage. But there are some phenomena that could result in high voltages (ferroresonance) which may be triggered by certain types of system failures.   

 

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