Metal Halide Ballast Question

[MikeNapoli]

I have 2 250 watt MHs and on one side the ballast is blowing fuses every other day.

I have them turning on at 1:00pm and off at 6:00pm .. only 5 hours of serious light.

Anyone know why only one side is doing it? And how I can fix it.

The fuses are 10 amp 250watt max. Should I go to a 10 amp 400 watt max? Do they make that?

 

[mfisher2112]

I'm far from an electrician, but if it is blowing a fuse, putting in a larger capacity fuse will just be asking for trouble in my opinion. Each one of those ballasts is wired independantly, so one blowing fuses and not the other is entirely plausible.

I would investigate the wiring for shorts, breaks, exposed wire to condensation/salt creep, etc. Something has to be causing that fuse to blow. That's what they are designed to do when there is a problem. Until you locate the problem, I'd unplug that ballast too.

Hopefully some electricians can chime in with more detail, but there definitely has to be something wrong either with the wiring, or internally on the ballast to be causing that fuse to blow so frequently.

 

[DaveK]

Most likely the ballast has a short in it. I have had this happen before. As pointed out by mfisher2112, it could be in the other wiring, so check that also.

Just to make sure it's not the bulb, swap the bulbs and see if the problem follows the bulb. If it does it's the bulb. If not it's the ballast.

Those are about the only two parts that can go wrong in a MH system. Most of the rest of the stuff, wiring, switches, and socket doesn't cause much in the way of problems.

If you have coil and core ballasts, and most commercial fixtures do, use this as a chance to replace those with electronic ballasts.

Electronic ballasts not only run cooler, they pay for them self in only about 2 years.

When making connections for lighting around a SW tank, I prefer to solider the wires together, then place a wire nut over the connection and tape. It's not strictly necessary, but it tends to keep and possible salt splash out.

 

[mfisher2112]

Good points, Dave. I didn't think about swapping the bulbs.

 

[mladencovic]

I have 2 250 watt MHs and on one side the ballast is blowing fuses every other day.

I have them turning on at 1:00pm and off at 6:00pm .. only 5 hours of serious light.

Anyone know why only one side is doing it? And how I can fix it.

The fuses are 10 amp 250watt max. Should I go to a 10 amp 400 watt max? Do they make that?

You are either reading something wrong :-\ or doing something wrong . 10 A fuse (or circuit breaker) if rated for 110V current CAN NOT be 250W or 400W max. 10A @ 110V is 1100W max. If it is indeed 10A 250W max, then it is either not supposed to be used with 110 V current or it is only 2.5A @ 110V. If you think of using stronger breaker then current, you have to make sure that your wiring can take extra Amps. Basically you will need a thicker wire. For example 14 gauge wire is rated only up to 15A and you will need 12 gauge wire for higher Amps.

I am currently in the process of rewiring my basement because of my tank. I have some idiot putting a garage, outdoor, part of the kitchen, laundry room and the basement on the same circuit breaker. It is 15A and when you add all the wattage in my tank, plus a few other things that are connected on the same breaker, it is fully maxed and 1500W. Every time someone would use the iron or a leaf blower, my circuit breaker would trip (oh did I mention that most critical of my PC equipment is in the basement :) So, at first, I thought I will simply replace it with a stronger 20A breaker) (4$ and 5 min work) but the wire leading from it is only 14 gauge and when I touched it, I could swear I could feel it warmer then the rest of the wiring in the same breaker box. And that is where the REAL DANGER is! So, now, I am splitting my tank from the rest of the stuff on that breaker, connecting it with the 12gauge wire and will use the separate breaker.

So, just be careful with what you are doing.