Lighting, Light Fixtures, Ceiling and Exhaust Fans - Bad transformer?

Having ongoing troubles with Kichler patio lighting system that came with the house I bought. There are five 11W walkway lights and a halogen (50W?)spotlight connected to a transformer that is plugged into an outdoor outlet with a light sensor wired to the outlet box. about two of the 11W bulbs burn out on a weeky basis. have dug up the wiring to see if it has frayed at all or if any connections were loose - no problems. my next guess was that the outlet box might be the problem, so i plugged transformer into a different outlet in my garage using an extension cord -- still lost two of the 11W bulbs over just a few days. what might be causing the bulbe to burn out so fast? will replacing the transformer correct things?

do you have the ability to measure the voltage each lamp recieves. I would suspect either a voltage problem or a moisture problem causing the premature failure.

If a heated lamp is exposed to water, it often caused it to burn out or even "pop" breaking the envelope.

There are few ways to slove this issuse with Low Voltage lighting system


1 ] The wire size to the low voltage lumiaires should be #12 or larger to prevent voltage drop

2] Some of the low voltage system do have multi tap connection like 11, 12 , 13 volts some case 14 volts as well

3] I know if some of the LV lumiaires are pretty close to the transformer the voltage will be some how higher than one on the end of the " line "

this list is one of few most common issue with low voltage lumiaires system and with some of the wires for pretty long run the voltage drop get very noticeable so you have to read the voltage at transfomer tap [ connection ] then go to first luimaire on the string and read the voltage then go to the end or last one on the string or line and read the voltage again and write it down and post it to us we can try to help ya with voltage drop and see where it goes and by the way please mention to us what size wire you have in the ground it should be a marking you may have to look around a little to find it.

once you find it please post it back here then we can go from there

Merci , Marc

Also, look under the cap of the transformer/switch to see exactly how much wattage it will handle. You have alot of wattage with 55 watts plus the 50 watts. Most of the ones I install max out at 72.

Thanks fdor all of the good suggestions. It looks like my wire is at least 12 gauge, and it looks like i'm getting 13.4 (rather than 12) volts at eack light in the set, including the halogen spotlight. My earlier post was wrong on the trotal watts though -- I have 5 11W and a 36W halogen. Is the 91 total watts too much for my transformer, and if so, do i need to have the spotlight on a seperate transfgormer? or is the 13.4V the issue? (i.e., time for a new 12V transformer? thanks.

We can't tell you that. You will have to look at the transformer to see how much total wattage you can have.

Some time you must have a light connected a minimum distance away from the transformer. There is voltage drop in the line the further you get from the transformer. They are designed to compensate for that and if you put light too close the voltage is too high.

Took many of the suggestions made and had been having good luck, until tonight. So thanks to all.

I was getting much more stability with the lights after I dug up the wiring and re-taped all of the connections to avoid some situations where I think moisture was seeping in. I also had switched from the 11W bulbs to 7W. Have been losing only 1 bulb every 10-15 days (instead of a few each week.) Much better than before. (The lights work off a sensor and are on all night, so i assume that a bulb burning out every couple of weeks is normal wear?) The only odd thing is that maybe once a week I think a bulb has burned out, but if I tap the light cover it comes back on. Odd, since the bulbs are seated tightly when I put them in.

HOWEVER, tonight I pulled a real bonehead move, and now have a more serious problem. I was using my new hedge trimmer and discovered (too late) that a loop of the lighting wire was above ground. I didn't cut through, rather, I apparently cut into the wire just enough to expose the copper. Without thinking I had grabbed the wire and must have twisted it just enough so that the +/- lines touched. A little smoke and a little melted wiring cover later, the lights (of course) went out. I unplugged the set and spliced the damaged wires back together, but am getting nothing now. None of the lights are working, though one of the 7W bulbs that I had pulled out didn’t seem to be blown. (It was a little “smoky” within the top part of the bulb, not black like it looks when a bulb does blow out, and the filament seemed to be intact. **sigh** after all of my hard work on this set, did I fry the transformer?