315 CMH Problem

mtnman2016

Well-Known Member
I have a 315 CMH that started failing a couple days ago and I am wondering if anyone here knows much about them. I have used for 2.5 grows veg thru flower with no problems until now.

Wat happens is that when it is cold it starts, then begins to get brighter then shuts down after about 1-2 minutes. After that, now it is warm, so it tries to kick back on in about 5-10 minutes. It starts then shuts down in about 2-3 seconds then just continues that cycle.

Could it possibly be a bulb? I don't have access to a spare and don't want to buy one if the ballast is shot. If it is the ballast, what could I look at? I have a multimeter, just don't know what to test.

FWIW, it is a cheap Chinese brand Amazon.com: TopoLite CMH 315W CDM 120/240V Grow Light Fixture Kit w/Bulb & 120V Plug Hydroponic Indoor Plants System (Enclosed CMH 315W(3100K Bulb)) : Patio, Lawn & Garden.

Edit: I just realized it is making a high pitch buzzing noise in the ballast, flickers, then shuts off.

Thanks
 
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