DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   Electrical and Wiring (
-   -   any rule of thumb for figuring max recommended bulb wattage? (

Philphine 07-03-2010 07:25 PM

any rule of thumb for figuring max recommended bulb wattage?
i'm kind of repurposing a ceiling light that uses 5 candleabra type bulbs. i've closing in on finishing and just realised i've forgoten what the recommended max wattage was. i brought 40 watt bulbs but then thought 5 bulbs together might add up.

i've had it on without problems, but i was just testing it (it's a ceiling light and i haven't installed it yet) so it was only on a few seconds.

so anyone know if i'm ok or should drop down to 25 watt bulbs? or a way to figure it out? thanks.

kok328 07-04-2010 08:21 AM

there should be a label on the light socket that indicates Max Wattage.

Philphine 07-04-2010 10:39 AM

i was about to wrie that there isn't one, but i went out and looked really close and there is something molded into the socket, 75w-125v.

i don't know if that's always applicable to whatever it's part of or if it's just for the socket it's self and there should be something else for the assembly that uses more of them.

i don't think i'll be trying 75 watters (i never seen candlelabra type bulbs rated that high anyway), but i'm hoping i'l be safe with the 40's unless someone says otherwise. thanks.

Wuzzat? 07-04-2010 05:56 PM


Originally Posted by Philphine (Post 46284)
i'm kind of repurposing a ceiling light that uses 5 candleabra type bulbs.

If a 200w flush mount ceiling fixture requires 90C wire in the ceiling box, assuming a 30C ambient temp. the thermal resistance of the fixture is (90-30)/200 = 0.3 C/W.

Post a photo of your fixture. If your house was built before 1985 the wire is probably 60C rated.

Philphine 07-05-2010 06:51 AM

the house was build i think around 1950.

an earlier pic from while i was working out the idea.

the original light had the 5 bulbs grouped together. i just spead them out. will that make a difference?

kok328 07-05-2010 08:57 AM

The wattage ratings are mostly for heat issues. With this spacing you'll be just fine with 40W bulbs.

Wuzzat? 07-05-2010 09:02 AM

For this setup the only limitation would be what heat your lamp sockets can stand, if they are plastic with a metal side contact. If they are they can probably stand 60w lamps as long as the lamp base is down and the lamp bulb is up.

kok328 07-05-2010 05:20 PM

You could consider CFL's that don't put out as much heat as incandescents do.

triple D 07-11-2010 09:47 AM

I think the deciding factor here is, what is the temp. rating of wire you used to wire fixture internally. Just curious, did you hook a grnd. tail to fixture? It looks like a pretty cool light, good luck...

Philphine 07-12-2010 08:27 AM

i need glasses. i can't read what's on it easily enough. i know it's 14ga. i got it from the maintenace shop at work and they hook up some fairly heavy duty stuff with it.

it has a ground. the black and white wires run around the inside of the tube and the green is screwed to the tube where the black and white wire come out.

just need some 1/8" plexiglass mirror i want to use as a medallion, and then i'll work on hooking it all up.

All times are GMT -6. The time now is 10:49 AM.