Electrical Advice
 

Sometime in the last week another ballast fried, that's three PFO and one Galaxy in the last two years. Staring to become more than simple bad luck. I have 2ea 20amp circuits to the tank then into 3ea Apex power strips. I've put a meter and test lamps on the circuits and everything seems to be fine, correct voltage, wired correctly etc. All the ballasts are protected from water, they aren't getting splashed on etc.

Any ideas?

Heat? Are the confined in a cabinet or anything at all?

They are inside the stand but not in a confined space. There's a lot of air around them. They shouldn't be getting too hot.

If they are in a cabinet and you are just counting on the ambient air to cool them without a fan blowing directly on them, then that's just wishful thinking. All MH ballasts get VERY hot, at least mine did. I had them in my cabinet mounted to one of the side doors and they would keep shutting down until I opened the door and put a small fan on them to cool them down.

I'd say add a fan to exchange the air the cabinet and promote better cooling of the ballasts. If the air in the cabinet isn't exchanged it will heat up from the ballasts and reduce the temperature difference causing the ballasts to run hotter. This will happen even if there is lots of space in the cabinet, it'll just take longer to heat up. There's not much else I can think off that cause premature failure although I would have thought the electronic ballasts would be less of an issue...

I'll give that a shot.

My sump has been off-line for a couple of months now so my temp probe from my Apex has been out of the water. According to my graphs the inside the stand doesn't seem to be going above 68F / 20C though

I know from experience that if the connections are not tight enough or if they are to tight they will draw more amperage and cause premature failure. At least that is what they say at work. Also we have had six Galaxy ballets fail right out of the box. They are running 250 watt 6500K MH bulbs.

Lost two more Galaxy ballasts in the last month or so. Time to make a decision about this damn tank.

go led:twised::twised::twised::twised:

Are these recent failures replacement ballasts, or more old units failing ?

Have you tried testing the supply voltage during start-up ? A voltage drop/low start-up voltage will fry a ballast over time

Have you opened any units to determine what is failing ? Capacitor/windings

Maybe a dumb question but, are you matching the recommended bulb types ?