Ballast changeout problem

[g-and-h_electric]

Another of my "dog" jobs.....

Went to a customer to changeout several bad ballasts . The fixtures are 8 foot HO, 120 Volt ones. Supply house sent me ADVANCE ICN-2s110's. Per the diagram on the ballast, they are direct wire color for wire color and wiring replacement. (40+ years in the trade, I would think I can do this!) Anyway, first fixture went fine, 2nd and 3rd fixtures not so well.

Installed the ballasts, and NEW tested lamps, still no light. The fixtures have power at them not only by testing, but they are in the middle of a row. Swapped the ballast, checked the wiring, and the sockets still nothing..... Called factory tech support (this good) 40 mins on the phone with them, and I got nowhere, other than "we are not electricians and cannot tell you how to wire these"

One more thing, the rows were powered down for installation, and the lamps installed BEFORE I powered the row back up

I have a hard time believing that 4 ballasts out of 5 are bad.

Any ideas?, I am stumped.


Howard

 

[kwired]

HO lamp sockets seem more prone to failures than non HO, did you check them?

If a series configuration one bad lamp socket or any other bad spot takes both lamps out of operation.

 

[g-and-h_electric]

Gave the sockets a quick visual, and they did not appear burned..... guess an ohmmeter check MIGHT be in order????? Are the plunger ends more prone to failure than the fixed ends? Been a long time since I have had issues merely changing a ballast!

 

[James L]

It's been quite a few years, but I had the same issue with a half dozen Advance HO ballasts in a body shop. I was completely stumped.

Called the supply house where I got them, and the guy asked if I turned off power before swapping. I said yes, then he asked if I turned breaker off.

I said no, turned off the switch.

He said that, for whatever reason, need to power off at breaker then back on.

I did that, and all the lights came on.

 

[synchro]

It's been quite a few years, but I had the same issue with a half dozen Advance HO ballasts in a body shop. I was completely stumped.

Called the supply house where I got them, and the guy asked if I turned off power before swapping. I said yes, then he asked if I turned breaker off.

I said no, turned off the switch.

He said that, for whatever reason, need to power off at breaker then back on.

I did that, and all the lights came on.

In a switch loop there's capacitance between the two wires that will cause some small leakage current to flow even though the switch is open. This is a WAG, but perhaps there's an "end-of-life protection circuit" in the ballast that's not being reset when the switch is off because of this residual leakage current, and the breaker needs to be off in order for a reset to occur.