wiring 3 lights to 1 switch – is this correct?
HI,
I hope everyone had a nice holiday!
We are installing 4 new can lights in our dining area. This will be added to the circuit, but I will be removing our microwave from the circuit to make sure there is room. I want to know how this should be wired. The power will be coming into light 1 (L1), and the switch will be wired off of L1 as well. So, there will be power coming in, wiring going out in one direction to the switch, and other wires going out in another direction to the other 3 lights. I have found wiring diagrams for a switch at the end of a run of 3 lights, but not like this. So, I adapted this to my situation, and I hope someone can double check this. This uses 14-3, not 14-2, for many of the runs.
At L1:
White wires from incoming power, light, outgoing power to L2 all connected
White wire from switch (labelled as hot) connected to incoming power black wire
Black L1 wire connected to red outgoing L2 wire
Black switch wire connected to black outgoing L2 wire
At L2:
Blacks from incoming from L1 and outgoing to L3 connected together
All whites connected together (incoming from L1, outgoing to L3, light)
Red from incoming from L1, red outgoing to L3, and black light wire connected together
At L3:
Blacks from incoming from L2 and outgoing to L4 connected together
All whites connected together (incoming from L2, outgoing to L4, light)
Red from incoming from L2, red outgoing to L4, and black light wire connected together
At L4:
White from L3 and to light connected together
Black from L3, red from L3, and black from light connected together
I’m also wondering if the 14-3 in necessary instead of using just all 14-2. Why would the above be preferred over using 14-2 for all runs if they lights are wired parallel? Does it cause any dimming effect or any sort of fire hazard? I’m pretty sure most of the wiring in my house where 1 switch operates more than 1 light it is using 14-2 and not 14-3. I’m hoping there is an electrical contractor here who will be able to answer.
Thanks everyone!
Ryan
Replies
You don't need the 14-3 going to the other lights -- 14-2 is sufficient. Also, apparently (if you're installing new wire) recent code requires 14-3 going to the switch (with the neutral/white left unconnected at the switch).
Black/white incoming from panel at L1. All whites connected together. Black incoming connected to black going to switch. Red from switch connected to L1 black terminal and also to black in 14-2 going out to L2.
At L2 connect whites together and to white from light. Connect blacks together and to black from light. At L3 connect black to black, white to white.
Note that this is a very simple circuit -- much simpler than a 3-way, eg. If you don't understand it you should probably get someone to help you.
Hi Dan,
Thanks for the info. So, no 14-3 is needed, except from light 1 to switch, and the white on this run is left unconnected at BOTH ends. All other runs are 14-2. Correct?
That's simple. I understand the wiring scheme. I had just read some other post on another website that was similar to this one, and it suggested the 14-3 method since the guy had had some dimming issues. So, I was wondering if there would be any issues for me. Is there an advantage of one over the other, I mean the 14-3 over the 14-2? Since it is all new, it doesn't matter which one I use, it's the same amount of work for me either way. They are both simple to wire, and I'd rather do whatever is the better of the two. So, if you have any more insight, I'd really like to hear it.
Thanks!
Ryan
Connect ALL whites together at L1. The supposed purpose (I'm told) of the white in the switch box is in case you ever install some sort of dimmer that needs a white connection. You want the white connected in L1 so that the dimmer can be installed without the need to open other boxes. Leave the insulation on the white in the switch box, screw a wire nut on the end, and fold it over in the back of the box.
There would never be a reason to run 14-3 to the lamps. The individual lamps should be connected "in paralllel" to each other, meaning that all their whites are connected together and all of their blacks are connected together -- no use for a 3rd wire.