Grounding fixtures with electronic ballasts?

[Zeke]

A Net search pointed this out to me. First I'd heard of it. Of course all instructions included with lighting fixtures tell you to ground the fixture. It's code. But I live in an old home and the light circuits are still knob and tube, no grounds.

So, troubleshooting a circular 22w-32w fluorescent shows no continuity thru the low voltage side of the ballast. I guess that says it's dead. It lasted a scant 3 years. Is the lack of grounding really the cause here?

The fixture is subject to internal heat due to the lens being modified with an antique glass cover. Maybe I need to provide some type of ventilation. The glass cover is 2wice as big as the original plastic lens.

This is the fixture:

This is kinda what I did:

 

[munkey]

Surely the lack of grounding isn't the issue here, right? The grounding wire is a safety feature designed to protect you from getting shocked if there's a wiring failure that energizes the metal case. I could be wrong, but I haven't heard about the lack of a ground interfering with normal operations. Heat sounds like a much more likely culprit.

Also, you said that "it's code," but my understanding is that if your circuit doesn't have a ground wire you can still replace existing fixtures and receptacles and ignore that aspect of the wiring, as they are grandfathered in.

 

[Zeke]

The issue here may be that some kind of field around the tubes needs a place to go. Someone said that if I touch the tube, the field energy will pass to me. I know one can hold a tube that is energized at one end and it will burn.

I'm wondering if the electronic ballasts are sensitive enough for this to be a problem and why so? The clips that hold the tube ARE well attached to the base with star rivets. That does tell me something.

I may have to snake a bare ground up there and over to a pipe.

 

[kbs2244]

I would go with the heat idea.
If it was a wireing problem it would not have worked in the first place.
You cooked it over time.