How many lights can I wire on one switch/circuit?

[Cobra4B]

Update - Turns out my kitchen lights, laundry room light, garage lights, and outlets for the garage door openers are on one 15 amp circuit. The kitchen has 12 60watt cans, the laundry room a single 4' 2-bulb fluorescent, hallway to garage 1 60watt can, and the garage only has a single 1/3rd horse opener in the center bay.

It appears that it's maxed out already. Figure 0.54 amps per can light (13), 0.9 amps per fluorescent (4 currently - 1 laundry 3 garage), and 5 amps for the garage door opener = 16+??

Update 2 - The 3 exterior lights over each garage door are on the same circuit too.

----------------------
I haven't tracked the panel to see what amp circuit this runs off. We bought the house early September and only one light worked. Today I swapped the T12 stuff out for new T8 and new T8 5000k bulbs. I'd like to add another 6 lights so I have 3 in each bay. Can I wire it all together, or will I need to add another switch/circuit? Not sure what amperage a typical T8 4' 2 bulb fixture pulls.

~Brian

 

[LS6 Tommy]

The ballasts should have cureent draw listed. You can go from there...

Tommy

 

[Platonic Solid]

Typical 4ft 2lamp F32T8 fixture draws 0.47A, thus you can put 25 of these on a dedicated 15A circuit. No additional switching required.

 

[Cobra4B]

Thanks all... need to figure out what all is on this circuit. Just checked the panel and nothing is labeled garage. Need to start flipping breakers and test.

 

[Speedy Petey]

Honestly, going from 3 fixtures to 6 in this case will almost certainly be no problem at all. You are adding less than 2A to a general purpose residential lighting circuit.

 

[Cobra4B]

I'd like to add 6 more for 9 total.

 

[Todd.Brock]

What you can add is solely dependent on what is currently being fed by that circuit. Add up what's there and you can increase up to about 80% of the circuit amperage. I agree with Pete though.

 

[zmaxmotorsports]

You need to find out what else is on the circuit,Normally Id wire garage lights on their own 15a circuit and the outlets on a couple of 20s.
Not everybody does it the same though.

 

[Cobra4B]

10-4 thanks all. I doubt the builder put the garage lights on their own circuit. Will need to figure out what all is fed on this circuit.

 

[James-W]

Personally, I think putting lights on more than one circuit is a good idea. That way if you do by chance trip a breaker, for whatever reason, you won't be in the dark.

 

[Dick in Wisconsin]

Personally, I think putting lights on more than one circuit is a good idea. That way if you do by chance trip a breaker, for whatever reason, you won't be in the dark.

2X that.

But when you're working in an existing garage with the walls all closed up, you're kind stuck. Unless you want to start adding wires and circuits.

 

[Cobra4B]

I think I'm maxed out as is. This circuit appears to have the following:

12 60 watt cans in the kitchen
1 60 watt can in hall
1 4' T12 fluorescent fixture in the laundry room
3 4' T8 fluorescent fixtures in the garage
3 lamps over each garage door
1 1/3rd horse opener and the other outlets over each bay

Seems like a lot on a 15 amp circuit does it not? When I was doing the light upgrade yesterday the wire looked beefier than 14.

 

[pattenp]

I think I'm maxed out as is. This circuit appears to have the following:

12 60 watt cans in the kitchen
1 60 watt can in hall
1 4' T12 fluorescent fixture in the laundry room
3 4' T8 fluorescent fixtures in the garage
3 lamps over each garage door
1 1/3rd horse opener and the other outlets over each bay

Seems like a lot on a 15 amp circuit does it not? When I was doing the light upgrade yesterday the wire looked beefier than 14.

Yep...that's fairly loaded up for a 15A circuit.

 

[Dick in Wisconsin]

I think I'm maxed out as is. This circuit appears to have the following:

12 60 watt cans in the kitchen
1 60 watt can in hall
1 4' T12 fluorescent fixture in the laundry room
3 4' T8 fluorescent fixtures in the garage
3 lamps over each garage door
1 1/3rd horse opener and the other outlets over each bay

Seems like a lot on a 15 amp circuit does it not? When I was doing the light upgrade yesterday the wire looked beefier than 14.

You need to calculate the amp draw.

Presume the breaker is a 15amp. If you look at the wire, you should be be able to tell on the sheathing if its 14 or 12. Unless you can readily ascertain all the wiring is 12, you're probably stuck with this being a 15amp circuit. Why would an electrician wire all this stuff with 12 gauge wire and put a 15amp breaker on the circuit.

That is quite a bit of stuff (number wise), but most of it is a low draw.

 

[Cobra4B]

Just checked up in the walk-in attic over garage. It's all 14/2... ****. I can swap the kitchen lights out to the new LEDs which I've been doing as they burn out. The equivalent LED is only 9.6 watts or 0.09 amps vs. 0.54 for a 60 watt if I'm doing my math correctly. So 13 cans at 0.09 each = 1.17 vs. 7.02 for the 60 watt.

 

[TorontoJeff]

The easiest way I know to add more on a circuit is to move to LED bulbs for your kitchen and hall. Rather than 60 watt, go to a 7 watt LED, and it will free up additional room. You still need to calculate to be sure, but if they aren't tripping the breaker currently, then you'll probably be fine with the additional fixtures if you swap out 7 of those 60 watt bulbs.