Install a larger ceiling fixture?
My 10 by 10 foot home office is wired for a 60 watt bulb. I’m going blind.
If I know where the circuit breaker is, how can I tell the strongest replacement fixture I put in this space?
Will the folks at Home Depot be able to send me home with the right thing or should I pay an electrician to install it?
For an ordinary residential 15 amp circuit, you can put up something with 8 75 watt bulbs and have 600 watts of light and only be at one-third the circuit total capacity. 
The folks at Home Despot ought to be able to help you. One word of caution-if you’re putting up a significantly larger and heavier fixture, the ceiling box may need to be upgraded to provide properly secure mounting.
A normal 15 amp circuit should be able to handle a higher wattage fixture with no problems, unless the circuit is already severely overloaded, which it will not be if the house was built to code.
The main restriction is the fixture itself. Many light fixtures have the maximum recommended wattage stamped on them. The reason for this is not the electrical load, but the heat buildup in the fixture. If you put higher wattage bulbs in a fixture rated for 60 watts you will get unwanted heat buildup which could damage the fixture and the wires and possibly start a fire.
I’m sure the folks at Home Depot will be more than happy to help you find a fixture that works for you.
You should be able to install anything you can buy at the store.
I’ve installed a bajillion lights (being an electrician and all) and have never encountered a situation where a (normal) fixture needed any special considerations, outside of fancy chandeliers and flourescent types of LARGE fixtures. Just get something within reason and you wont have any problems. (Try not to go over two 75 watt bulbs in any one fixture, the heat buildup can be bad for the wiring regardless of the insulation on the back of the fixture.)
Or, you can get the fixture that will take two 75 watt bulbs and then swap them out for the flourescent equivolents (they’ll run cooler). Just remember that you can’t dim a flourescent bulb.
Make sure the circuit is off and that you inspect the wires inside the box for signs of heat damage and or stress. If you see cracks in the insulation or anything that looks suspicious its time to call a pro.
If you want to direct the light to a certain area of the room you can get the kind of fixtures with dual adjustable heads on them that you can aim at the desk or at some other strategic location in the room.
Actually, one third of a 15 amp circuit would be 480 watts.
Since the question has been answered, can I ask what a potato has to do with it? I am seriously 
He used potato to extract broken bulb from fixture. Old trick. Other thread in GQ>
Another thread asked how to remove a broken light bulb from a socket. Among other suggestions was to make sure the power is cut, then jam a potato (or clay) into the socket to give you enough grip to uncrew the remains of the bulb.
Oh, I saw the thread but didn’t click on it. Wow, that’s really cool. I’ll have to remember that.
No, at 120 V, a 15 A circuit has a capacity of 15 x 120 or 1800 W, one third of which is 600 W. Unless you’re working with 96 VAC, in which case, you’d be absolutely correct.
I knew I’d catch a fish.
Let’s see if anyone else is familiar with the NEC before I give the reason why it IS 480. 
You refer to the 80% derating the NEC requires for continuous loads–which I believe is defined as one operating for three (or maybe two (?) ) hours, no? Think yer clever, eh? 
That’s close, in the residential parts of the code it gives you the actual allowable loads for home wiring. The 80 percent you are aware of is for all other circuits in general, there are exceptions for the residential circuits that don’t take into account continuous loads, they just flat out tell you 1440 watts for a 15 amp circuit (80 percent).
Interesting. My question is, what’s the point of derating? Ok, I understand they want margins for safety and all that, but why not include the safety factor in the construction and materials? After all, once the electrician’s done his job and gone home, nothing is stopping the homeowner from maxing out the circuit if he wants to, anyway. I’ve never gotten a satisfactory answer to this question. Maybe you’ve heard one.
I guess it’s because you have to draw the line somewhere. If they pushed everything to the edge, you’d have breakdowns all the time. In actuality a 15 amp wire could probably handle 25 amps or more for a sustained time (without the insulation breaking down), but we feel safe operating it at much less than that.
The weakest link theory. With all the variables in a whole house electrical system it’s nice to know that your wiring is designed to be the strongest link.
Derating isn’t so important in a home, I’ll give you that. In a setting where you have multiple conductors in an enclosure or raceway it becomes very important, as you have the possibility of heat build up and heat retention where the stability of the insulation can become suspect.
Plus, if we were to design all circuits to be right at the edge of the overcurrent devices trip setting you’d have all kinds of nuisance tripping.
If someone were to wire a home in such a way that they were loading a 15 amp circuit to 1800 watts the breaker would always be at the verge of tripping.
You probably wouldn’t need the furnace in the winter as the wires running through your home would heat it. 
I can’t imagine that your office is wired for 60 watts. I don’t think that woule even be legal.
What you probably have is a 15-amp circuit breaker, with #14 wire, going to a fixture labeled with a 60-watt limit. So the wiring can handle 1800 watts, but the fixture is limited to 60. And it’s limited because of heat – anything larger than a 60-watt incandescent will overheat the fixture.
So that’s your clue there – 60-watt incandescent.
The cheapest & easiest thing you can do is replace the bulb with a compact fluorescent bulb. This will run much cooler than an incandescent, so it can go in that same fixture that is there now. And a 26 watt fluorescent will product about the same light as a 100-watt incandescent. You can even go to a 32 watt (=150 watt light) or a 40 watt (=200 watt light).
I’d certainly try this before going to the expense & effort of replacing the fixture!
Well, I’ll definitely try that first. Thanks!
Uncommon Sense, I’d like to request a cite on your 80% or 1440 calculation. Everything I see in Articles 220, 240, and 310 leaves me with the impression that for 1 and 2 family dwellings, so long as there aren’t more than 3 current carrying conductors in a raceway or cable assembly, I need not derate the allowable ampacity of the circuit. If I’ve missed something, kindly advise. 
Also, brush up on article 210.
It references in several places the 125% (.80) rule, the 180VA rule (per outlet)and Article 210-24 references table 210-24 witch references the permissible loads as directed under article 210-30(a).
We are to believe that you are allowed a minimum of 180 VA per outlet (light, plug, etc.) and the breaker that protects the circuit must be rated at 125% of the continuous load. Since the circuits in question are limited to table 310-16, 14 guage wire is rated for 15 amps and since the overcurrect device can’t exceed that and it must be rated at 125% of the contiuous load at 180 va per device you are, in essence, limited to 1440 watts per circuit (15 amp) and 1920 watts per circuit (20 amp).
Further, oultets allowable on a 15 amp circuit using the 180 VA rule and the 125% rule. 1440/180 = 8, and 1920/180 = 10.6 (I round down to 10).
Sorry, in a hurry, might not make sense to most, let me know if you have any questions or if it doesn’t make sense.
I will have more time this afternoon to quote more articles.