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dcalabro
Best practice wiring order

Is there a best practice for the wiring order if connecting a light switch and electrical outlet on the same circuit? For example should the feed from the breaker go to the light switch first or the outlets? The reason i ask is because in one room the light dims when i use my drill.

A. Spruce
Re: Best practice wiring order

To be honest, I don't think it matters how you wire the switches and outlets on a circuit, though lighting and outlets are supposed to be on separate circuits so that when you overload an outlet and blow a breaker, you don't lose your lighting to find your way to reset it.

Whether or not you can eliminate flickering/dimming is questionable, I think it has more to do with how the circuits are wired at the panel than how they are connected throughout the house.

Fencepost
Re: Best practice wiring order

Even though it's permissible, I don't like the idea of feeding a circuit through a receptacle (where the incoming wire connects to one screw and the outgoing wire connects to another). I prefer to connect the wires with a wire nut, with a single pigtail to the receptacle.

I'm not sure why I feel this way, it just seems like a better way to do it for some reason.

dj1
Re: Best practice wiring order

Try plugging your drill in other places. Do you get the same dimming?

JLMCDANIEL
Re: Best practice wiring order

An excessively long run of undersized wiring is most likely the problem. While it may be a 15 amp circuit line drop may have been taken into consideration.

Jack

Re: Best practice wiring order

With 2011 Code a neutral must now be present in every branch circuit switch location, even if it's not being used, with very few exceptions. This is to allow use of an occupancy sensor in the future.

So, running power to the switch location is now a smart move. If you have a 3 way or 4 way switch circuit you either have to run 4 wire romex or MC cable etc. or supply power to the other 3 way (and 4 ways), from the same branch circuit.

This of course has nothing to do with your dimming problem.

Good Luck from Columbiana, Alabama
Maurice Turgeon, http://thesemi-retiredelectrician.com

dcalabro
Re: Best practice wiring order

***, a few pieces of information here.

Voltage drop is something I did not take into account here. I know the current light and outlet are on a 15a running over knob and tube.I am planning on upgrading the room with this problem to be on its own 20a circuit for the outlets and the light on a 15a to phase out the k&t.

My question now applies to voltage drop because the branch feed from the breaker to the first outlet on the 20 amp circuit will be about 50 ft then another 10 feet to the last outlet for that circuit. Am I ok with 12ga or should I be running 10ga to the first outlet then use 12ga to branch off to the remaining 2 outlets?

Same question applies for the 15a lighting circuit, same 50ft branch to switch but then about 20ft for lighting of ceiling fans in other rooms. I'm now thinking I should use 12ga throughout for this but would I be ok with 14/2?

Regarding the 2011 code adjustments. I planned on running power directly to the switch with lets say 12/2 then I will run 12/3 from switch to ceiling fan to assume separate control of fan vs light. Don't I already have the neutral from the feed at the switch or are you saying that the 12/3 needs to be 12/4?

canuk
Re: Best practice wiring order
dcalabro wrote:

***, a few pieces of information here.

Voltage drop is something I did not take into account here. I know the current light and outlet are on a 15a running over knob and tube.I am planning on upgrading the room with this problem to be on its own 20a circuit for the outlets and the light on a 15a to phase out the k&t.

Ah -- that explains a lot.

My question now applies to voltage drop because the branch feed from the breaker to the first outlet on the 20 amp circuit will be about 50 ft then another 10 feet to the last outlet for that circuit. Am I ok with 12ga or should I be running 10ga to the first outlet then use 12ga to branch off to the remaining 2 outlets?

You're fine with the 12 ga. -- no need to go larger.

Same question applies for the 15a lighting circuit, same 50ft branch to switch but then about 20ft for lighting of ceiling fans in other rooms. I'm now thinking I should use 12ga throughout for this but would I be ok with 14/2?
You're fine with the 14 ga

Regarding the 2011 code adjustments. I planned on running power directly to the switch with lets say 12/2 then I will run 12/3 from switch to ceiling fan to assume separate control of fan vs light. Don't I already have the neutral from the feed at the switch or are you saying that the 12/3 needs to be 12/4?

You're fine running the supply feed to the switch location because the neutral will be there. This is my perfered method of running a circuit for a light .

Re: Best practice wiring order

I've been running 12-4 rather than 12-3 between 3 way switches so I'd have a neutral in both boxes, which is now required.

But,there are other ways to do it

Good Luck from Columbiana, Alabama
Maurice Turgeon, http://thesemi-retiredelectrician.com

JLMCDANIEL
Re: Best practice wiring order
dcalabro wrote:

***, a few pieces of information here.

Voltage drop is something I did not take into account here. I know the current light and outlet are on a 15a running over knob and tube.I am planning on upgrading the room with this problem to be on its own 20a circuit for the outlets and the light on a 15a to phase out the k&t.
Generally speaking voltage drop doen't come into play unless your run is over 100 feet, or a heavy load is used. Ths can easily happen with a single 15 amp circuit feeding multiple lights and recepticles.

My question now applies to voltage drop because the branch feed from the breaker to the first outlet on the 20 amp circuit will be about 50 ft then another 10 feet to the last outlet for that circuit. Am I ok with 12ga or should I be running 10ga to the first outlet then use 12ga to branch off to the remaining 2 outlets?
You should have no proble with 12 ga here
Same question applies for the 15a lighting circuit, same 50ft branch to switch but then about 20ft for lighting of ceiling fans in other rooms. I'm now thinking I should use 12ga throughout for this but would I be ok with 14/2?
Again you should have no problem here.
Regarding the 2011 code adjustments. I planned on running power directly to the switch with lets say 12/2 then I will run 12/3 from switch to ceiling fan to assume separate control of fan vs light. Don't I already have the neutral from the feed at the switch or are you saying that the 12/3 needs to be 12/4?

In this case you would have the required neutral at the switch.

Jack

farmer52
Re: Best practice wiring order

The lights and outlets may be on individual breakers but I'd bet they share a neutral.(The white wire) If you pull a seperate ground for each circuit, the flickering should be eliminated.

Note, If they do have a shared neutral, you can still have power on the white even though you have the breaker off. i.e. Find the feed to the room. Turn off the breaker for the outlets. Disconnect the white and see if the lights go out. If they do, you have another breaker using that neutral. You are also working live so be careful not to touch anything. You shouldn't depend on a breaker being turned off to have a dead wire anyhow. Always test the wire for voltage before you touch anything.

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