Some Days I'm a Troubleshooting Genius...

[Sparky555]

...and some days I'm a zero.

I've got a commercial fixture on a residence that's giving me fits. It's a ground level flag-pole light, 70W multi-vapor that I changed a bulb & ballast kit last December. Now the thing is striking, staying on a few seconds, then turning off for a minute or two. It's not downstream of a GFCI, but uses the same cct.

To further confuse the issue the interior GFCI trips with nothing downstream but an exterior non-used duplex-no load on either outlet.

Help!

Dave

 

[mdshunk]

If it's an HPS, it is probably cycling on the end of life as they do. That's my best guess at the moment anyhow. I like to change pretty much everything out to MH and steer wide of using any multi-vapor products if I can avoid it.

The GFCI tripping troubleshooting needs to start with a megger check. I have certainly found exterior receptacles full of insect nesting material and even "morning dew" to the point that the GFCI will trip. The megger check before and after the receptacle replacement proves this out. You might also want to tone out that GFCI load side to be sure that's the only thing that's on the load side. History tells me there's a pretty good chance other stuff is on it, regardless of what the customer said or you think you found out.

 

[Sparky555]

The GFCI & duplex are back-to-back, clean and new (silicone caulked & dry). Thanks for the tip on MH.

Dave

 

[Loffgren]

re

re

Sounds like the Lamp on/off etc..

 

[bjp_ne_elec]

Mdshunk - what particular megger do you prefer for the T/S you decribe in recent thread regarding the GFCI issue? I need to add a megger to my "tool set", and I just was reading one of the links. Haven't used a megger since an apprentice, and it was to meg out a ground grid. It was one of those high end units.

Thanks

Dave

 

[mdshunk]

Mdshunk - what particular megger do you prefer for the T/S you decribe in recent thread regarding the GFCI issue? I need to add a megger to my "tool set", and I just was reading one of the links. Haven't used a megger since an apprentice, and it was to meg out a ground grid. It was one of those high end units.

Darned near anything will do the trick for troubleshooting purposes. I guess guys have had pretty good results from the Fluke 1507 lately, but I don't think you even need to go that fancy just to use it as a troubleshooting tool. Something like the Extech 380260 or the Supco M-500 would suffice for general troubleshooting.

 

[Sparky555]

BTW Marc, the megger testing is a great idea for the exterior light wiring. I plan on testing the underground wires tomorrow. I don't use the megger enough. I have a Megger MIT330.

Dave

 

[JohnJ0906]

Darned near anything will do the trick for troubleshooting purposes. I guess guys have had pretty good results from the Fluke 1507 lately, but I don't think you even need to go that fancy just to use it as a troubleshooting tool. Something like the Extech 380260 or the Supco M-500 would suffice for general troubleshooting.

I have the Extech 380260, and it has sufficed for the basic troubleshooting I need it for - things like you have described.

 

[weressl]

...and some days I'm a zero.

I've got a commercial fixture on a residence that's giving me fits. It's a ground level flag-pole light, 70W multi-vapor that I changed a bulb & ballast kit last December. Now the thing is striking, staying on a few seconds, then turning off for a minute or two. It's not downstream of a GFCI, but uses the same cct.

To further confuse the issue the interior GFCI trips with nothing downstream but an exterior non-used duplex-no load on either outlet.

Help!

Dave

If the light cycles, you have a bad bulb.
If the light tuns off because the GFCI trips?
Disconnect the light and see it the GFCI trips.
If not then connect a load to the receptacle and see if the GFCI holds.
If it does not trip with the light disconnected and another load on - for an overnight - then you narroved down to the ballast/light/photocell(?).

 

[Sparky555]

Thanks. The wiring tested fine and replacing the bulb seems to have taken care of the cycling. If I had more commercial experience I would have know that. I hope this bulb lasts more than 6 months. The GFCI tripping w/o a load is still a mystery. I changed the exterior duplex to a GFCI (it was wired downstream of the interior GFCI) to figure out which outlet is causing the trip if it happens again.

Dave

 

[weressl]

Thanks. The wiring tested fine and replacing the bulb seems to have taken care of the cycling. If I had more commercial experience I would have know that. I hope this bulb lasts more than 6 months. The GFCI tripping w/o a load is still a mystery. I changed the exterior duplex to a GFCI (it was wired downstream of the interior GFCI) to figure out which outlet is causing the trip if it happens again.

Dave

Make sure that the bulb is designed to the burning position in the fixture. Even the small wattage discharge bulbs should last at least 10000 hours.

As far as GFCI goes adding a GFCI receptacle to a GFI Circuit Breakers circuit is a waste of money. You already ARE protected by the breaker. Leakage can develop anywhere in the wiring, a nicked conductor in the ground or in the underground conduit can over time develop enough leakeage to trip. As the moisture changes in the ground the trip will be randomly occuring. Wet JB, water getting into the receptacle can all cause trip.

 

[Sparky555]

Make sure that the bulb is designed to the burning position in the fixture. Even the small wattage discharge bulbs should last at least 10000 hours.

As far as GFCI goes adding a GFCI receptacle to a GFI Circuit Breakers circuit is a waste of money. You already ARE protected by the breaker. Leakage can develop anywhere in the wiring, a nicked conductor in the ground or in the underground conduit can over time develop enough leakeage to trip. As the moisture changes in the ground the trip will be randomly occuring. Wet JB, water getting into the receptacle can all cause trip.

It's not a GFCI cct, the exterior duplex was downstream of the interior GFCI. Now they're individual. I took it apart & everything is dry as dust with some recent rain.

dAVE