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jshimmin
02-18-2009, 02:54 PM
Customer called and said that their lights were staying on. The photocell was installed 4-5 months ago so I installed a new one. After a day of use, the new one was doing the same thing.
I tested the oginal one on the bench and it works flawlessly.

The photocell controls 8 Fluorescent line voltage fixtures. It is mounted on the side of the unit that houses the transfomer/ballast for the first fixture in the run. They pull a little over 100 watts when on.

Has anyone seen any issues with mounting a photocell near the transformer/ballast?

I used the original photocell on a low voltage transformer on the property and it has worked fine.

INTEGRA Bespoke Lighting
02-18-2009, 06:02 PM
Many Fluorescent Ballasts / Lamps are not compatible with Photocells and Motion Detectors. This is probably the root of the issue you are experiencing.

S&MLL
02-18-2009, 09:38 PM
8 dollar Home depot one?

Lite4
02-19-2009, 12:55 PM
Many Fluorescent Ballasts / Lamps are not compatible with Photocells and Motion Detectors. This is probably the root of the issue you are experiencing.

That is interesting James, I did not know that. Why is this do you suppose? I had always regarded photo and motion controls simply as open/closed switches. Is there a variablity in current flow with the Fluorescent fixtures that effects the switches?

jshimmin
02-19-2009, 02:38 PM
I swapped out the unit for a different style that has a ground connection on it. I cycled it through several times and it appears to be operating normally. Time will tell.

INTEGRA Bespoke Lighting
02-19-2009, 10:22 PM
Tim I really don't have the specifics to offer you but I have seen this mentioned on the packaging of CFL and FL lamps in the past. I don't use any FL products myself, but about 5-6 years ago I came across a situation where the client had switched incand. to FL and complained that the photocell was not working. Ended up having to install an astro timer to solve the problem.

Lite4
02-19-2009, 10:36 PM
Ok, thanks James. Just curious is all.

INTEGRA Bespoke Lighting
02-19-2009, 10:48 PM
A-Ha! here are some specifics for you guys:

Problem: The lamp won't light.

Possible Cause: Some photocell and timer controls don't use a relay or electrical contact to turn and off the power. Instead, they use a solid state electronic component - usually a triac - to control the power flow. Unfortunately, triacs don't allow 100% of the electricity to flow through when they are conducting, and this can interfere with the electronics in the compact fluorescent lamp base. If the compact fluorescent lamp works correctly in another socket that is controlled from a wall switch, this could be the problem.
Source: http://nemesis.lonestar.org/reference/electricity/fluorescent/trouble.html

Lite4
02-19-2009, 10:50 PM
That makes sense. Thanks James.