2

Our kitchen wiring is getting updated because right now we are running everything off of two circuits. The electrician recommended we put a 4-wire system in versus a 3-wire since he will be pulling new wire anyways. How it was sold to us is that it would eliminate our need for GFCI outlets in the kitchen, which would save us money. Obviously the cost of a few outlets would't add up to the 4-wire system upgrade.

My questions is, is it worth the extra money to run a a 4-wire versus just leaving it as a 3-wire? What would be the benefits?

4
  • Are you counting the ground as a wire, or not? 4C+E is very uncommon. You likely need GFCIs no matter what, it's just whether they're in the board or on sockets. Nov 23, 2016 at 6:04
  • 4 wires is good when you want/need to run a GFCI protected pair (from the load side of the GFCI outlet) and a non-GFCI protected pair in parallel. (For when the fridge is at the end of the line) Nov 23, 2016 at 10:46
  • Yes -- are you counting the ground as a wire? (/2/2 NM is fairly common these days, and would make sense in your application, BTW) Nov 23, 2016 at 20:17
  • I don't know how that gets you out of the code requirement for GFCI outlets ? and GFCI is easy to put in - buy one receptacle and feed the others from it, $10 and anyone can install one - my sister who is not an electrician can do it, so you can too.
    – Ken
    May 31, 2021 at 14:56

2 Answers 2

3

FYI, a "cable" is a bundle of several wires.

Yes, that's a good move - run "four wire" cables (I assume you're talking about /3 wire i.e. 12/3 or 14/3, the fourth wire is the ground wire. If you're talking /4 or /2/2 or 4 wires plus ground, same logic still applies.)

The real cost here is the labor to engineer the layout and drill the holes and fish the cable and do the ugly nasty pulls. The extra cost of a cable with 1 more wire is pretty small compared to his labor. It's a smart idea even if the extra wire is simply unused. It can be used later.

I don't know how your contractor is pricing things. I personally find GFCI breakers to be annoyingly more expensive than GFCI receptacles, though GFCI breakers are a tiny bit safer. Your electrician should certainly know that you only need one GFCI receptacle per circuit. If your kitchen has 12 double receptacles fed off 3 circuits, you only need 3 GFCI receptacles. They "feed" the other receptacles in the circuit.

In the /3 cable (4 wires with ground), that third wire (red) allows you to add an entire second circuit with just one more wire. The trick is called a "multi-wire branch circuit" and is wired in a special way that allows the second circuit to "share" the neutral (white) and ground (bare) from the first circuit.

In the /4 or /2/2 wire (5 wires with ground), you can have 2 complete circuits in the same cable. Two circuits can share a ground wire.

0

I'd stick with the "3 wire" as you call it (meaning 12/2 or 14/2 wire, having a black and white insulated wire and a bare copper wire in the jacket for ground). It doesn't really make sense to run /3 wire, unless you are doing something with 3 way switches or receptacles where one outlet is switched and the other always on.

As Someone Somewhere stated in the comments, you'll have to still GFCI protect this either at the panel or a receptacle.

1
  • yes the code still requires GFCI in the USA and one outlet must be within 24 inches of any point on the countertop, and if you have a 20 inch counter to the edge - you need a receptacle..
    – Ken
    May 31, 2021 at 15:01

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.