Using Self-Contained Fluorescent Lamps

[kray1300]

What's the concensus on these fluorescent lamps? Do we treat a 13 watt fluorescent as a 13 watt or as a 60 watt, since that is what it replaces? In other words, if a fixture says it is limited to a 40 watt lamp, can I use a 13 watt fluorescent which "replaces a 60 watt bulb"?

What about their use in recessed cans?

 

[jamesguy10]

Yes, if it uses 13 watts its a 13 watt bulb. Light output is not measured in watts. Its a comparison.

 

[480sparky]

Wattage is a measurement of power consumption. "P" or "W" in Ohms Law. The 'brighness' of the bulb, or how much light it produces, is measured in lumens.

 

[mdshunk]

When a customer has a fixture that's limited to a 40 or 60 watt lamp, and they really want a 100 watt lamp in it, I reccommend to them that they get one of the 20-somthing watt CF's. Same amount of light as a 100 watt incandescent, but won't burn up the fixture or socket.

 

[winnie]

How about this one: the fixture might be fine with the bulb, but the bulb may not be fine with the fixture.

Some of these CF lamp must be in ventilated fixtures, and can't take the heat build up of an enclosed fixture.

Be sure to read the label on the lamp...and keep a copy of the warranty information! I use CF lamps, I like CF lamps. But we gotta hold the manufacturers to reasonable quality control, especially for bulbs that are supposed to last years.

-Jon

 

[peter d]

I'm amazed at how hot some CFL's get. They don't get quite as hot as incandescents but pretty close. If it's only a 13 watt CFL for instance, why would it get so hot??

 

[480sparky]

Some CF bulbs are rated only for certain orientations as well. Some can only be used base down, so they shouldn't be put in can lights or track heads.

 

[LarryFine]

I'm amazed at how hot some CFL's get. They don't get quite as hot as incandescents but pretty close. If it's only a 13 watt CFL for instance, why would it get so hot??

Two reasons:

1. The electronics of the ballast.

2. The mercury vapor is conducting electric current.

The smaller the light, the less surface area per watt there is to dissipate heat. A 13w fluorescent has much less than 1/3 the surface area of a 40w fluorescent.

 

[mdshunk]

I'm surprised that nobody ever mentions the fact that most incandescent fixtures not only list a maximum wattage, but also list the lamp type. For instance, it might say, "Max 60 watt A-19 lamp". I'm not sure if a CFL qualifies as A-19 type or not. Sorta doubt it.

 

[peter d]

I certainly don't like self-ballasted CFL's to begin with. I definitely don't like them in a recessed light.

But then again, there are many of them in service without a problem so I'm not sure what to think of them. I'll take an incandescent for the time being.