Dual Ballast T-5 Light Problem

[Modifieddriver]

Finally have my shop lights wired.

I used Lithonia IBZ 654 high bay fixtures with six HO 54 watt bulbs.

There's one 4 bulb fixture, IBZ 454, on a separate switch, for an initial shop walk-in light.

Then there's 17 dual ballast 6 bulb fixtures. Five in one light bank and six each in two other light banks.

Each light bank has two switches. One switch controls two bulbs per fixture and the other switch turns on the other four bulbs.

Now, here's the problem:

I have two lights where the four bulbs will come on, stay on for several minutes and then stop working. All four bulbs, sometimes three, will stop working. I changed bulbs, but that didn't help.

Is this an indication of a bad ballast? How do I check?

I have several more fixtures, so I could swap out the entire fixture or just change a ballast out.

Suggestions??????????????

Also, here's a pic of the lay out. This is a 2,400 sq. ft. area. With all the lights turned on, it's bright . All on gives me something like 170+ CL. The way things are wired gives me flexibility in such a large area.

 

[Aceman]

The first thing to check is the wiring. Verify it's wired correctly by reading the ballast diagrams, also make sure you have no loose connections. Tug on every wire at every connection.

Just because it came from the factory prewired doesn't mean it's right.

 

[Modifieddriver]

Thanks. Like other "stuff" these are made south of the border.

We'll try what you say.

Thought maybe the symptoms would indicate something else.

 

[StayThirsty]

holy **** thats a lot of light! Jelous here.

 

[Modifieddriver]

Yes, it's bright in there!!!!!!!!!!!

Best expenditure I made. Plus the flexibility of tuning the # of bulbs on is a bonus.

I changed out the one light fixture with the bad ballast.

 

[monkeybar]

Ballasts may be overheating for reasons unknown yet, and thermal overloads within them open to prevent fire.

Check wiring of those which quit after certain time on. Check current draw of those especially, compare it to the good ones; if higher, problem causing overheating exists.

JMO. monkey