# Can you run a junction inside an outlet or recessed light

I have been working on finishing my basement and am starting my rough in electrical. I am learning as I go and have gotten most of the basics down.. calc load, box size, stapling, supports etc.

One thing I cant figure out is if you can have a junction within a live outlet or recessed light. Ideally I would like to run a Y from my last recessed light can with one line going right, to a receptecle and one going left, to the end switch. I am guessing this is against NEC code but have been unable to find out for sure, partly because I am unsure of the correct terminology for it.

Can someone point me in the right direction? Is this even called a junction? or is it called something else like a branch?

I am getting a pro to do some of the finish connections but I am doing all of the rough in.

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ok thanks. From the responses below it appears the only limiting factor is box size and possibly accessibility. This will make doing the rough ins a lot easier. thanks – user2883390 Nov 12 '13 at 5:49

Modern recessed lights have junction boxes built in.

Similarly on a new work recessed fixture

You are free to daisy-chain other lights or receptacles, so long as you connect properly and do not exceed the number of wires for the size of the built in box. A chart to calculate this can be found here.

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Hi, I know I can daisy chain. I am asking about splitting/junction/Y connect in a box, not daisy chaining. I am using the above H7ICT halo box – user2883390 Oct 24 '13 at 3:40
If by splitting/junction/Y connect you mean power in on one cable, and two (or more) fixture wires out, tying all the blacks together, all the whites together and all the grounds together, yes. – bib Oct 24 '13 at 11:38

According to the National Electrical Code (NEC), there are only two factors that limit you.

# Conductor box fill

If you're working with standard sized boxes, you can use Table 314.16(A) to determine the number of conductors allowed in a box.

If you're using non-standard boxes, you'll have to make the calculations yourself. Basically, it works like this.

### Conductor Fill

• For each current carrying conductor (ungrounded (hot), or grounded (neutral)) that terminates or is spliced within the box, add 1.
• For each conductor that passes through the box without splice or termination, add 1.

### Clamp Fill

• If there are any internal cable clamps, add 1 (not 1 per, just 1).

### Support Fittings Fill

• If there are any luminaire studs or hickeys, add 1 (not 1 per, just 1).

### Device or Equipment Fill

• For each yoke or strap containing one or more devices, add 2.

### Equipment Grounding Conductor Fill

• If equipment grounding conductors enter the box, add 1 (not 1 per, just 1).

## Volume Allowance Calculation

Use this Table 314.16(B) to calculate the total box fill.

• Sum up the count from the `Conductor Fill` section, and multiply by the value from the table. For example: If you had 4, 14 AWG conductors, you'd multiply 4 by 2.00.
• Sum up the counts from the `Clamp Fill`, `Support Fittings Fill`, `Device or Equipment Fill`, and `Equipment Grounding Conductor Fill` sections, and multiply by the value from the table of the largest conductor in the box. For example: If this value was 4, and the largest conductor in the box was 12 AWG. You'd multiply 4 by 2.25.
• Add the 2 totals together. For example: Using our values above (4 x 2.00 + 4 x 2.25 = 17), you'd need a box with a volume of 17 in. cubed.

# Wire Connector Capacity

If you're using twist-on wire connectors, each connector can connect a specific number and size of conductors (Check manufacture documentation). This will limit the number of wires connected together. If you're using push-in wire connectors or terminal blocks, you'll be limited by the number of terminals.

# tl;dr

If you want to supply multiple devices downstream; but the devices are in opposite directions, there should be no problem splicing multiple cables together to feed the devices.

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Your question is not clear at all. Yes you can "split" inside a junction box, as long as you keep the connections within the limit allowed by the NEC per box volume. -Running a "y"- is not a term used by electricians, but by plumbers. Yes you can "run a Y" in a J box if I know what you may mean

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