Metal Halide lamps

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Disgusted of T Wells

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Hi

Does anyone know if a 70W HID lamp will work properly in a 150W fitting.

The lamps in question seem to strike ok but then after 15- 20 mins random lamps start cycling. The fittings are marked up at 150w. But 70w lamps were fitted when I got there. I have tried fitting like for like but the fault recurred

(just after I off-hired the scaffold).

 
No, Mr. T. Wells. They won`t work correctly.

The control gear is expecting to hold the arc for a 150W light. It possibly doesn`t think the 70w is lit, thermals out, and then re-ignites. The other possibility is the igniter itself. If this is in the control gear, rather than integral to the lamp, it could be continuing to attempt ignition, thermally tripping, causing lamp outage, then re-starting after cooling off.

I`d try a 150w lamp, and see how it goes! :)

It has also occurred to me that, if the lamps are SON, the 70W variants often have internal ignitors. I don`t know what would happen if a lamp with internal ignition were fitted to control gear containing an igniter too?????!

HTH

p.s. Welcome aboard.

KME

 
Welcome Disgusted,

I use a lot of metal halide lamps but always with the lamp wattage matching the fitting wattage, so just because 70watt were fitted dos'nt make it right. I'm really not sure on this. Did the fittings have sodium lamps originally ? Some older ones will not support metal halide lamps . When you say you fitted like for like do you mean you fitted 150watt and got the same fault ?

Deke

 
Deke

The fittings are hi level downlight spots in a church hall, I dont know for sure what was in there originally since the church members have relamped it themselves for 10 yrs, but due to the application probably always been metal halide. I was provided with a sample to source the replacement lamps (70w) so that is what I fitted. But with the benefit of hindsight I that was probably a little rash.

 
Its possible fittings are damaged metal halide fittings need lamps replacing when they go or ignitors can be damaged. Welcome to the forum disgusted. Are you from tunbridge wells.

Batty

 
Think the worst part is if it's a church hall could eat a serious chunk of their budget to rehire a platform and buy more lamps!

 
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