How do you check output voltage on a ballast?

[itsamyheff]

I have posted a few times recently about bulbs and pfo ballast. I started noticing the left bulb seemed to be a little less bright than the right. I thought it was just time to replace it. I posted asking if the pfo ballast would fire the radium bulb. I got a used radium bulb and installed it. It did fire, but it still was dim compared to the other side. I switched them, and that same side still dim. So my question is, how do you check the output? Is it time to replace the ballast? Do you know of any parts to replace to fix this problem? Thanks.

 

[crewdawg1981]

could it be the light fixture thats to blame not the ballast?

 

[mustangcaleb]

you can get a voltage reader thing, you plug it in, then plug the ballast into it and itll tell you how much its pulling. i saw it on the "other" reef site in a discussion about the odyssey lights. i can prob find the thread if youd like me to

 

[totalchaos13]

tongue... hehe!

 

[rjrgroup]

:lol2:I just hope nobody attempts it!

Totalchaos13;627951 wrote: tongue... hehe!

 

[itsamyheff]

I didn't think about checking the socket. I will trade them out and see if that makes a difference.

Edit: I may have stumbled on that info on the other site. But if you can look it up to verify, that would be great. thanks.

 

[ichthyoid]

I have a high voltage probe for my Fluke DMM. The starting voltage for MH 250 & 400 watt bulbs is somewhere around 500 volts. and the operating voltage is below 150, according to the article below. I could rig up a test point in your lights and we could check them, if your socket or wire is not the problem. I also have a clamp-on ammeter probe as well, which would be a simpler way to see an electrical imbalance between ballasts.

:headbang:

 

[itsamyheff]

I swapped the sockets and the dim side moved to the other. It is in the ballast.:yuk:

 

[mustangcaleb]

theres pics of it on the first page

 

[ichthyoid]

itsamyheff;628063 wrote: I swapped the sockets and the dim side moved to the other. It is in the ballast.:yuk:

I'm confused, if you swapped the sockets and the problem followed them, isn't the problem in the socket? Just checking.

 

[itsamyheff]

update: opened up the ballast, checked capacitors, found one to be bad. Now to locate one and replace. Thanks ichthyoid for the help.

 

[ichthyoid]

Larry, you are very welcome. Glad I could help.

FWIW- I came across a good site for reference on reef lighting. It showed which ballasts will fire what bulbs, among other juicy tid-bits.