250 watt MH fixture problem


I have a customer who has us stop by every 6 months or and clean up his high bay fixtures, plus we swap out a 3Rd of the bulbs each time, the place is a trash transfer station and the fixtures get rather nasty after awhile.

Well in the process of cleaning them one of my guys slipped and dropped the bulb into the high lift and it shattered, no big deal it's a $9 bulb, well she replaced the bulb and finished the row, turned on the power and the fixture she re-lamped wasn't firing up properly, after a few minutes the power was cut and the fixture checked out.

Turned out the 250 watt bulb that shattered was replaced with a 400 watt bulb, ok mistakes happen, the bulb was replaced with the correct one and the power was turned back on.

Now a larger problem, all the new bulb did was produce a pretty blue arc through the tube, but it never fired up.

So we pulled the fixture and bench it, I determined it has three parts, an old school magnetic ballast, a cap and a starter, the ballast doesn't look damaged and it doesn't stink and has no open windings, it is wired for 277 VAC, the cap tests good and the starter I do not know how to test, as a note the starter has three conductors, 2 across the bulb and 1 connected to the ballast.

I'm leaning toward the starter being pooched, but was hoping someone here might have come across something similar and could provide some tips as to what I might have overlooked or how to test the starter.

I really don't want to eat a $250 fixture, but it is my responsibility to get it working or replace it, because we ruined it.

And just to make things more fun my local supply house, which is using the term loosely, doesn't carry any starters, the counterman didn't even know what one was, so I will have to source that part online.

Also the new bulb was tested in another fixture and it does fire up properly, so the problem is something in the fixture.

The good news is the customer isn't pushing to get this resolved NOW, but it still needs to be resolved and it's my job to do it.

Any thoughts, advice or ideas would be greatly appreciated.



Staff member
You're going to need a ballast replacement kit, or just by an LED lamps
and bypass the ballast.


Electron manager
You using pulse start lamp? If it has an ignitor it is a pulse start system. Metal halides all use same ignitor from 50 to 450 watts from what information I have seen.


Senior Member
I don't bother trying to troubleshoot HID lamps down to a component level. Get a ballast kit and new lamp, change it all out and it will work for years.

Little Bill

Staff member
Depending on the age of the components and bulb, I will sometimes just replace a bulb. But most of the time I will put in the kit that was mentioned. Most of these lights are a pain to get to and I don't want to....

1.) Have to go through the trouble of getting back up there soon after I just worked on it

2.) Have the customer think I don't know what I'm doing when the next part fails a week after I just replaced a different part.

If a customer balks on me replacing the whole "guts" along with a bulb, I explain that I'm already here and you pay only one service charge. If I have to come back in a week, month, months, etc., you will pay a service call for each trip. Plus, if there is a lift rental in play, it is certainly a "no brainer" to fix everything at once.


Senior Member
Ballast kit for that is maybe $50?

You can order igniters though. I keep some on the bucket truck for lot light servicing. If you’re doing this a lot it’s not a bad idea to keep some in your stock.

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