I have an unattached garage that we wired for electricity a couple years
ago. I had a semi retired electrician consult and it was all inspected
and passed. I had three cheap fluorescent 4 foot fixtures in the
ceiling. The lighting circuit is on a 15 amp breaker and a 15 amp GFI
outlet. That's code and the inspector was fine with it.

Then last year one of the fixtures died and I replaced that setup with
six four-foot units that were more durable, and filled 'em with T8 32W,
daylight spectrum.

The light is great. Except now, after the lights are on for a while -
more than two hours, I think - if I turn them off, and then right back
on because I forgot something, the gfi trips. If I wait a few minutes it
won't trip. If I turn off two or three of the fixtures, it's usually
okay but sometimes still trips. I replaced the gfi outlet with one of
HD's "Heavy Duty" units. That lasted a little longer.

From some experimenting, I thought I had it narrowed down to one fixture
so I switched the bulbs out of that one with another, but now it seems
to be random. If three fixtures are off, the gfi doesn't trip. It's hard
to be sure because after a few minutes, the gfi doesn't trip any more.
I've had them on all day and everything's fine unless I turn them off
and then back on.

Anybody got any thoughts? I'm thinking I might have to run another wire
on another 15 amp circuit, and have two switched banks of three fixtures
each. But maybe I can get away with replacing all those fixtures. That
would cost more money that running another circuit up there, but I'm not
looking forward to crawling around running more wires and outlets and a
new switch. But maybe that's the only way.

Think it's the fixtures? Or am I just running too many fluorescents for
on gfi to handle?

Dan

If the lights are on the "load" side of the GFCI outlet, remove them and
install them on the "line" side. There is no NEC requirement to protect them
through GFCI



"Dan" wrote in message
.. .
I have an unattached garage that we wired for electricity a couple years
ago. I had a semi retired electrician consult and it was all inspected
and passed. I had three cheap fluorescent 4 foot fixtures in the
ceiling. The lighting circuit is on a 15 amp breaker and a 15 amp GFI
outlet. That's code and the inspector was fine with it.

Then last year one of the fixtures died and I replaced that setup with
six four-foot units that were more durable, and filled 'em with T8 32W,
daylight spectrum.

The light is great. Except now, after the lights are on for a while -
more than two hours, I think - if I turn them off, and then right back
on because I forgot something, the gfi trips. If I wait a few minutes it
won't trip. If I turn off two or three of the fixtures, it's usually
okay but sometimes still trips. I replaced the gfi outlet with one of
HD's "Heavy Duty" units. That lasted a little longer.

From some experimenting, I thought I had it narrowed down to one fixture
so I switched the bulbs out of that one with another, but now it seems
to be random. If three fixtures are off, the gfi doesn't trip. It's hard
to be sure because after a few minutes, the gfi doesn't trip any more.
I've had them on all day and everything's fine unless I turn them off
and then back on.

Anybody got any thoughts? I'm thinking I might have to run another wire
on another 15 amp circuit, and have two switched banks of three fixtures
each. But maybe I can get away with replacing all those fixtures. That
would cost more money that running another circuit up there, but I'm not
looking forward to crawling around running more wires and outlets and a
new switch. But maybe that's the only way.

Think it's the fixtures? Or am I just running too many fluorescents for
on gfi to handle?

Dan

On Sat 30 Dec 2006 04:20:50p, "RBM" rbm2(remove
wrote in :

If the lights are on the "load" side of the GFCI outlet, remove them
and install them on the "line" side. There is no NEC requirement to
protect them through GFCI


Well that would certainly make it simple. :-)

And yes, they're on the load side. Okay, I'll do that tomorrow.

Thanks RBM.

"Dan" wrote in message
.. .
I have an unattached garage that we wired for electricity a couple years
ago. I had a semi retired electrician consult and it was all inspected
and passed. I had three cheap fluorescent 4 foot fixtures in the
ceiling. The lighting circuit is on a 15 amp breaker and a 15 amp GFI
outlet. That's code and the inspector was fine with it.

Then last year one of the fixtures died and I replaced that setup with
six four-foot units that were more durable, and filled 'em with T8 32W,
daylight spectrum.

The light is great. Except now, after the lights are on for a while -
more than two hours, I think - if I turn them off, and then right back
on because I forgot something, the gfi trips. If I wait a few minutes it
won't trip. If I turn off two or three of the fixtures, it's usually
okay but sometimes still trips. I replaced the gfi outlet with one of
HD's "Heavy Duty" units. That lasted a little longer.


Lasted a little longer but also give you *less* protection.


From some experimenting, I thought I had it narrowed down to one fixture
so I switched the bulbs out of that one with another, but now it seems
to be random. If three fixtures are off, the gfi doesn't trip. It's hard
to be sure because after a few minutes, the gfi doesn't trip any more.
I've had them on all day and everything's fine unless I turn them off
and then back on.

Anybody got any thoughts? I'm thinking I might have to run another wire
on another 15 amp circuit, and have two switched banks of three fixtures
each. But maybe I can get away with replacing all those fixtures. That
would cost more money that running another circuit up there, but I'm not
looking forward to crawling around running more wires and outlets and a
new switch. But maybe that's the only way.

Think it's the fixtures? Or am I just running too many fluorescents for
on gfi to handle?

Dan

Why not just connect the fixtures to the existing lighting circuit in the
first place? Either connecting to the line side of the GFI, as RBM
suggested, or to the lighting circuit will make the tripping go away but you
still have a stray ground leak somewhere enough to trip the GFI. What you
describe is not easy to troubleshoot. Its not your lamps and its not that
you have too many fixtures connected either, assuming you have no other
additional loads. Recheck you connections, the neutral in particular. Could
also be a bad fixture.

Dan wrote:
I have an unattached garage that we wired for electricity a couple years
ago. I had a semi retired electrician consult and it was all inspected
and passed. I had three cheap fluorescent 4 foot fixtures in the
ceiling. The lighting circuit is on a 15 amp breaker and a 15 amp GFI
outlet. That's code and the inspector was fine with it.

Then last year one of the fixtures died and I replaced that setup with
six four-foot units that were more durable, and filled 'em with T8 32W,
daylight spectrum.

The light is great. Except now, after the lights are on for a while -
more than two hours, I think - if I turn them off, and then right back
on because I forgot something, the gfi trips. If I wait a few minutes it
won't trip. If I turn off two or three of the fixtures, it's usually
okay but sometimes still trips. I replaced the gfi outlet with one of
HD's "Heavy Duty" units. That lasted a little longer.

From some experimenting, I thought I had it narrowed down to one fixture
so I switched the bulbs out of that one with another, but now it seems
to be random. If three fixtures are off, the gfi doesn't trip. It's hard
to be sure because after a few minutes, the gfi doesn't trip any more.
I've had them on all day and everything's fine unless I turn them off
and then back on.

Anybody got any thoughts? I'm thinking I might have to run another wire
on another 15 amp circuit, and have two switched banks of three fixtures
each. But maybe I can get away with replacing all those fixtures. That
would cost more money that running another circuit up there, but I'm not
looking forward to crawling around running more wires and outlets and a
new switch. But maybe that's the only way.

Think it's the fixtures? Or am I just running too many fluorescents for
on gfi to handle?

Dan

Could be on the re-light the load is a bit inductive, are these
all-electronic ballasts or the heavy ones with a fair number of
transformer windings?

Getting zapped by an overhead light is unlikely, but unlikely stuff
happens, so leaving it connected through the GFCI is for me a
no-brainer.

Dave

It's not required by NEC, and if the lighting circuit is properly grounded,
he's perfectly safe


wrote in message
ups.com...

Dan wrote:
I have an unattached garage that we wired for electricity a couple years
ago. I had a semi retired electrician consult and it was all inspected
and passed. I had three cheap fluorescent 4 foot fixtures in the
ceiling. The lighting circuit is on a 15 amp breaker and a 15 amp GFI
outlet. That's code and the inspector was fine with it.

Then last year one of the fixtures died and I replaced that setup with
six four-foot units that were more durable, and filled 'em with T8 32W,
daylight spectrum.

The light is great. Except now, after the lights are on for a while -
more than two hours, I think - if I turn them off, and then right back
on because I forgot something, the gfi trips. If I wait a few minutes it
won't trip. If I turn off two or three of the fixtures, it's usually
okay but sometimes still trips. I replaced the gfi outlet with one of
HD's "Heavy Duty" units. That lasted a little longer.

From some experimenting, I thought I had it narrowed down to one fixture
so I switched the bulbs out of that one with another, but now it seems
to be random. If three fixtures are off, the gfi doesn't trip. It's hard
to be sure because after a few minutes, the gfi doesn't trip any more.
I've had them on all day and everything's fine unless I turn them off
and then back on.

Anybody got any thoughts? I'm thinking I might have to run another wire
on another 15 amp circuit, and have two switched banks of three fixtures
each. But maybe I can get away with replacing all those fixtures. That
would cost more money that running another circuit up there, but I'm not
looking forward to crawling around running more wires and outlets and a
new switch. But maybe that's the only way.

Think it's the fixtures? Or am I just running too many fluorescents for
on gfi to handle?

Dan

Could be on the re-light the load is a bit inductive, are these
all-electronic ballasts or the heavy ones with a fair number of
transformer windings?

Getting zapped by an overhead light is unlikely, but unlikely stuff
happens, so leaving it connected through the GFCI is for me a
no-brainer.

Dave

On Sun 31 Dec 2006 03:26:02p, "# Fred #" wrote in
:


Why not just connect the fixtures to the existing lighting circuit in
the first place?

I don't understand. They ARE connected to the existing lighting circuit,
installed by a licensed electrician.

Either connecting to the line side of the GFI, as RBM
suggested, or to the lighting circuit will make the tripping go away
but you still have a stray ground leak somewhere enough to trip the
GFI. What you describe is not easy to troubleshoot. Its not your lamps
and its not that you have too many fixtures connected either, assuming
you have no other additional loads. Recheck you connections, the
neutral in particular. Could also be a bad fixture.


No additional loads. Nothing but six fluorescents. To answer Dave's
question, hey're new, and they're not very heavy. I don't know for sure
whether they're all-electronic but suspect they are.

I used that little three-light tester on every outlet on that circuit,
and it indicated the wiring was correct. I've run continuity checks on
the ground wire (after disconnecting it from the box) and it all says
the ground is connected, and there's no continuity between the ground
and the other two leads.

I'm stumped in that regard. Not sure what to test now. I've got an amp
meter and have been checking the amperage on the lamps. They're all
running at about .5 amps.

When you say "a bad fixture", do you mean one of them could be leaking
some voltage to ground only when warm and only after being turned off
and then back on? That was my first thought, and I think I'll continue
with that line.

Thanks.

"# Fred #" wrote in message
. ..

"Dan" wrote in message
.. .
I have an unattached garage that we wired for electricity a couple years
ago. I had a semi retired electrician consult and it was all inspected
and passed. I had three cheap fluorescent 4 foot fixtures in the
ceiling. The lighting circuit is on a 15 amp breaker and a 15 amp GFI
outlet. That's code and the inspector was fine with it.

Then last year one of the fixtures died and I replaced that setup with
six four-foot units that were more durable, and filled 'em with T8 32W,
daylight spectrum.

The light is great. Except now, after the lights are on for a while -
more than two hours, I think - if I turn them off, and then right back
on because I forgot something, the gfi trips. If I wait a few minutes it
won't trip. If I turn off two or three of the fixtures, it's usually
okay but sometimes still trips. I replaced the gfi outlet with one of
HD's "Heavy Duty" units. That lasted a little longer.


Lasted a little longer but also give you *less* protection.


From some experimenting, I thought I had it narrowed down to one fixture
so I switched the bulbs out of that one with another, but now it seems
to be random. If three fixtures are off, the gfi doesn't trip. It's hard
to be sure because after a few minutes, the gfi doesn't trip any more.
I've had them on all day and everything's fine unless I turn them off
and then back on.

Anybody got any thoughts? I'm thinking I might have to run another wire
on another 15 amp circuit, and have two switched banks of three fixtures
each. But maybe I can get away with replacing all those fixtures. That
would cost more money that running another circuit up there, but I'm not
looking forward to crawling around running more wires and outlets and a
new switch. But maybe that's the only way.

Think it's the fixtures? Or am I just running too many fluorescents for
on gfi to handle?

Dan

Why not just connect the fixtures to the existing lighting circuit in the
first place? Either connecting to the line side of the GFI, as RBM
suggested, or to the lighting circuit will make the tripping go away but
you still have a stray ground leak somewhere enough to trip the GFI. What
you describe is not easy to troubleshoot. Its not your lamps and its not
that you have too many fixtures connected either, assuming you have no
other additional loads. Recheck you connections, the neutral in
particular. Could also be a bad fixture.

Agree. Take the fixtures off of the GFI; but be sure all of the fixtures
are well grounded. What I think is happening is that one or more of the
ballasts in the fixtures has a high impedance leak to ground. But, some
leakage is normal and actually is required to start the lamps in some types
of fluorescent circuits. If there is a failing ballast, grounding it will
eventually solve the problem as the ballast will fail dead or trip the CB.
Ballasts have internal thermal cut-outs; so there is minimal risk of
overheating or fire as the ballast fails.

It sounds like the ballast fault may be temperature sensitive -- not a
surprise if the fault involves a capacitor inside the ballast.

TKM

On Mon 01 Jan 2007 01:29:34p, "TKM" wrote in
:
It sounds like the ballast fault may be temperature sensitive -- not a
surprise if the fault involves a capacitor inside the ballast.


I agree it certainly seems temp related. It only happens when the lights
are on for at least a couple hours.

Going on the assumption that it's a faulty cap or transformer and that
it's probably just one fixture out of the six, I'm going to buy a new
fixture and begin swapping them out one at a time and see what happens.
I installed them in a way that makes it easy to remove and replace each
one. I should have done that before I posted here. Maybe I was looking
for someone to agree that it sounded like a bad fixture. :-\

I and that electrician I hired spent a lot of time installing that
circuit. I was very careful, he made the final hookups, we put the
tester on every outlet in the lighting circuit, and the inspector
approved the setup. I will continue to look for faults in the grounding,
but I took extra time to make sure the white, black, and ground wires
were where they're supposed to be when we ran that circuit because I
didn't want to go crawling around those garage rafters again, chasing
problems. I think the chances of it being faulty wiring are slim.

Thanks all. Still open to suggestions. :-)

If one of the fixtures isn't the culprit, it will probably take a few
weeks to know for sure because I won't be spending lots of time in that
garage for a while. Would you like me to post back with what I come up
with?

Dan

"Dan" wrote in message
.. .

Thanks all. Still open to suggestions. :-)

If one of the fixtures isn't the culprit, it will probably take a few
weeks to know for sure because I won't be spending lots of time in that
garage for a while. Would you like me to post back with what I come up
with?


Don't buy a whole new fixture. Just replace the ballast(s). Cheaper, and
it's the only part in a flourescent light that might actually go bad.

I would get the electronic ballasts from a local electrical supply shop, not
Home Cheapo or other big-box place. They are a little more expensive than
magnetic ballasts (but cheaper than a whole new light), they are more
efficient (hence run cooler) and start almost immediately with no flicker or
buzz. However, cheap brand-x units sometimes do buzz. Good ones will not.

Also, since this is in a garage, make sure you get ballasts rated for the
coldest temps you are likely to get.

"Dan" wrote in message
.. .
On Sun 31 Dec 2006 03:26:02p, "# Fred #" wrote in
:


Why not just connect the fixtures to the existing lighting circuit in
the first place?

I don't understand. They ARE connected to the existing lighting circuit,
installed by a licensed electrician.


The way I read your original post, you had two circuits with one for
lighting and one for receptacles that is protected by GFI. Perhaps I
misread. In any case, its better to have lighting and receptacle loads on
different circuits if its all practical. Easier to troubleshoot and you
won't have a receptacle load take out your lights in the middle of the
night.