ballast problem? only works for seconds

I have a 400 w ballast capable of running both a hps and a mh. when I first plug it in. it hums, and the light comes on, but it all shuts off after a few seconds. lights off and humming from ballast stops. I decided to try to switch the bulb. I switched from mh to hps. the hps worked for maybe 3 mins and then shut off. I turned it on again, it only ran a minute.
Also, before it started all this I noticed that while its running I can hear a sorta electrical buzzing coming from several appliances in my house. Not on the same circuit.
Any thoughts?

Sounds like a grounding issue either in the ballast or on that specific circuit.

Does it work when plugged into a different circuit in the house?

-spek

I will give that a try later. this circuit was just put in a few months ago and is only running this 400w light and the fan. Going to check a diff outlet and maybe open the ballast up and look. it came prewired. Ill post back here later tonight. thanks.

Alright, so I have checked it on a different circuit, still having problems. I checked the wiring to the light fixture. I decided it most likely was in the ballast. I opened it up, it looks like there is a bunch of melted plastic running through it. The way the plastic looks like it is dripping makes it look like it came from the top of the electronics board. The last one has a close up of the thing it looks like the plastic came from. Still really unsure, maybe this is normal?

I'd check the board for cold soldier joints. Be carefull though. If there's an open circuit those electrolytic capactors will still be charged. In other words look but don't touch. caps have a number followed by (uf)microhenries usually printed next to the caps voltage capacity. Getting zapped by a hot cap is alot like being tazored by police.

Do you by chance have a multimeter?

is it a 220 ballast on a 110 outlet maybe?

I do not have a multimeter. The ballast says "voltage range 110-240v." it is in a 110 outlet. did you see the pictures? Does that black stuff everywhere look normal?

I think the black stuff is a not so good attempt at a conformal coat for the PCB- it is supposed to be there for the protection of the PCB. As to what is causing the failure you mention- I have no idea. It would seem as thought the starter is establishing an arc, but there is insufficient current flowing to maintain the arc after it is started. Bad ballast.

The black stuff is a type of potting compound that is applied to such devices for several reasons:
1. Prevent competitors from reverse engineering the board.
2. Prevent the unit from being repaired.
3. Insulate the electronic components so that they run hot and fail earlier.

From what I can tell, this ballast is a super-cheapie china digital. Failure of such units should be expected.

Well. thanks for the input. I bought a new ballast. different brand. has a longer warranty. it works. and now nothing in my house buzzes. so I'm glad I got it. still have the old one and would love yo fix it if its an easy fix. but I don't think that's the case. anyway thanks.

nicktater said:

Well. thanks for the input. I bought a new ballast. different brand. has a longer warranty. it works. and now nothing in my house buzzes. so I'm glad I got it. still have the old one and would love yo fix it if its an easy fix. but I don't think that's the case. anyway thanks.

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Take it to a hydro shop tell them to test it for you. Explain to them the issues you were having. Maybe they can diagnose it.

fir3dragon said:

Take it to a hydro shop tell them to test it for you. Explain to them the issues you were having. Maybe they can diagnose it.

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This is the best advice for people that have not studied electronics.