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#21563 - 02/05/03 10:02 AM Mercury Vapor light problem
rayh78 Offline

Registered: 11/11/01
Posts: 26
Installed a 100 watt mercury vapor outdoor light. It was fine until winter now its going thru bulbs. Problem started when customer is using a small electric space 1500watt heater on inside on same circut.
Is it a defective fixture or to much on circut.

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#21564 - 02/06/03 03:27 PM Re: Mercury Vapor light problem
golf junkie Offline

Registered: 04/22/01
Posts: 511
Loc: York, NE
What voltage do you have at the light with both the heater and light drawing current??


#21565 - 02/06/03 06:50 PM Re: Mercury Vapor light problem
rayh78 Offline

Registered: 11/11/01
Posts: 26
did not check, assumed if it was drawing to much would trip breaker

#21566 - 02/06/03 08:00 PM Re: Mercury Vapor light problem
nesparky Offline

Registered: 06/21/01
Posts: 650
Loc: omaha,ne
The 100 watt light draws about.9 amp (100W/110V=.9091A)
The 1500 watt space heater draws (1500w/110v=13.6364A)
total draw is 14.5455A
A 20 Amp breaker will carry this all day.
A 15 amp breaker will propally carry this if the heater does not run all the time.
If 14AWG wire was used and the heater and light are over50-75' away you propably have a voltage drop causing the light to pull more than normal. If so the bulb will heat up more than normal and burn out much to soon.
You need to do a voltage check at the circuit breaker feeding this circuit and at the heater and at the light. Be careful and use a good quality meter. Avoltage drop of greater than 5% is a problem.
You may need to seperate the heater and light. Also check if anything else is on the circuit.
Good luck

#21567 - 02/07/03 05:50 PM Re: Mercury Vapor light problem
Trumpy Offline


Registered: 07/05/02
Posts: 8532
Loc: SI,New Zealand
One thing I do know, is that any type of Gas
Discharge lighting, does not particularly like Voltage drop, it can damage the control gear as well as the lamps.
If possible, I would put the MV Lighting on a dedicated circuit.
Hope this helps.
Let's face it, these days if you're not young, you're old - Red Green grin


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