hps lamp

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laketime

laketime

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I am getting a reading of about 80v at the socket is that correct? The fixture is rated for 70w but the customer had installed 100w. I installed 70w lamp but it won't fire up. Bad fixture?
 
HIDopencircuitvoltages.jpg

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laketime said:
I am getting a reading of about 80v at the socket is that correct? The fixture is rated for 70w but the customer had installed 100w. I installed 70w lamp but it won't fire up. Bad fixture?
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With HPS and other pulse start fixtures you need to make sure the ignitor is firing also. I make sure to use my Fluke 335 on these fixtures, the screen will flash when hit with the pulse while testing for socket voltage. I'm sure Fluke would NOT recommend this practice. Another guy in the shop blew his UAEI(?) meter up when he did the same thing....

I've been tempted to buy those screw in ballast testers, but haven't done so yet.
 
laketime said:
Nice! I just replaced the guts of the fixture and it worked. Would a 100watt lamp in a 70 watt rated HPS fixture cause the igniter to fail?
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Yes. If an HPS lamp does not light, the ignitor will fail eventually because it will continue to try to light the lamp.

When troubleshooting any HID fixure with an "ignitor, or starter" (HPS, pulse start metal halide, or metal halide 150w and lower) needs to be removed from the circuit to test "open circuit voltage" , or a capacitor used with a multimeter.
Remember to only use a TRUE RMS meter when testing these.
 
laketime said:
Nice! I just replaced the guts of the fixture and it worked. Would a 100watt lamp in a 70 watt rated HPS fixture cause the igniter to fail?
Click to expand...

Id pick this book up too, "advances guide to HID lighting" its just a little pocket guide, and you can download the pdf version too.
 
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