What is "14/2/2 double neutral" and what is it used for?

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mnoone

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I have been calling around trying to find a roll of NM 14/4. A local shop says they have "14/2/2 double neutral". My understanding is that 14/4 is black, white, red, blue, bare and 14/2/2 is black, white, red, white with red stripe, bare. I asked the shop to confirm if the second white was striped on the "14/2/2 double neutral" and they took a look at the cable and said both whites were unstriped.

Is this a thing? Why would they not stripe one of the wires?

Also, similar question - is my understanding right that 14/4 is meant for 3 way switches (to stay compliant with 2011 NEC) and 14/2/2 is meant for running two separate circuits?
 
14/2/2 was created after AFCI breakers came into the picture. Every manufacture I have used has one white wire with a red stripe.
We use a lot of it for residential projects.

Also commonly use 14/2/2 for 3way/4way switches. Black/white for power and red/white w/red stripe (phased with tape or sharpie) for travelers.
 
curt swartz said:
14/2/2 was created after AFCI breakers came into the picture. Every manufacture I have used has one white wire with a red stripe.
We use a lot of it for residential projects.

Also commonly use 14/2/2 for 3way/4way switches. Black/white for power and red/white w/red stripe (phased with tape or sharpie) for travelers.
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I'm sorry I'm missing something here - what does 14/2/2 have to do with AFCI breakers?
 
mnoone said:
I'm sorry I'm missing something here - what does 14/2/2 have to do with AFCI breakers?
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Solves the issue of running two 120V circuits that used to be done with a 3 wire cable and a MWBC. AFCI does not support MWBC. Also can be used for 2 GFCI circuits without paying the big price for 2-pole GFCI.

Mark
 
mnoone said:
I'm sorry I'm missing something here - what does 14/2/2 have to do with AFCI breakers?
Click to expand...
Unlike traditional MWBCs, the neutral cannot be shared (even on a different phase or leg) unless the AFCI breaker is two pole (the same dilemma with GFCI). 14/2/2 became more popular around the advent of AFCIs, to run two circuits in one pull with proper wire insulation indication.

Two pole AFCI breakers are more expensive and less common:
1698687444598.png
 
In the past we would run a multiwire branch circuit and share the neutral. Sometimes that shared neutral may not be required to be on an afci so running 14/2/2 is giving you 2 separate circuits to do whatever you please.
 
This is a solution for MWBC with AFCI requirements. Most AFCI even GFCI won't work on the typical MWBC shared neutral so wire companies made a 2 hot 2 neutral cable. Not the same as 14/4 cable - 3 hot and 1 neutral.

Now there are some mfg. that are making an AFCI to function with a typical MWBC but most still not working with it.

Also have used 12/2/2 or 14/2/2 to pull new circuits up to a hard to fish in area to get 2 circuits with one pull.
 
mnoone said:
I have been calling around trying to find a roll of NM 14/4.
Click to expand...
What do you need it for 3 phase? Controls?
I usually see it stocked in MC or Tray Cable but not NM.
Some types of tray cable can be used like NM now, I had a roll of 'joist pull' tray cable we used for going from the outdoor unit to indoor units on ductless heat pump installs. Seems to be more robust than NM and also listed for damp locations.
 
tortuga said:
What do you need it for 3 phase? Controls?
I usually see it stocked in MC or Tray Cable but not NM.
Some types of tray cable can be used like NM now, I had a roll of 'joist pull' tray cable we used for going from the outdoor unit to indoor units on ductless heat pump installs. Seems to be more robust than NM and also listed for damp locations.
Click to expand...

For 3 phase they have 14/4nm

14/2/2 has a black / white and a red/ white with red tracer

Looks like this

1698708828917.png
 
tortuga said:
What do you need it for 3 phase? Controls?
I usually see it stocked in MC or Tray Cable but not NM.
Some types of tray cable can be used like NM now, I had a roll of 'joist pull' tray cable we used for going from the outdoor unit to indoor units on ductless heat pump installs. Seems to be more robust than NM and also listed for damp locations.
Click to expand...

They used to supply tray cable with some brand of the mini split units. Hvac guys would install it and I would make them pull it out as it was not listed for use without a tray or conduit (I believe). I guess the industry jumped on that right away. TC looks just like SE cable if I remember it correctly so it was odd that it wasn't listed for residential indoor use.
 
Dennis Alwon said:
They used to supply tray cable with some brand of the mini split units. Hvac guys would install it and I would make them pull it out as it was not listed for use without a tray or conduit (I believe). I guess the industry jumped on that right away. TC looks just like SE cable if I remember it correctly so it was odd that it wasn't listed for residential indoor use.
Click to expand...
Yeah I am guilty as charged for allowing it back then, I think the Joist pull 'JP' rating was unnecessary red tape.
The list of things I like about tray cable are numerous;
  • Conductors are individually marked 75C THHN - THWN-2.
  • Insulated green EGC, is handy for entering older panels with lots of exposed live parts.
  • Heavier sturdier jacket than NM or SE.
  • Stranded conductors are handy for 10 AWG and larger.
 
Siemens afci plug-on neutral 1-pole will work with 3 wire MWBC. there's no neutral terminal on the breaker. The panel has typical neutral bar. I used a couple WMBC in a house and used individual Siemen AFCI plug-on CBs and didn't even use handle tie. I knew the inspector wouldn't catch it.
 
mnoone said:
I have been calling around trying to find a roll of NM 14/4. A local shop says they have "14/2/2 double neutral"
Click to expand...
Is there a reason the color matters so much?

I used 14/2/2 for MWBCs when I wired a fitness center. I re-identified the white w/red tracer, using it as blue
 
I think it could also be used for 3-way switching where the new code rule requires the neutral be brought to the switch. It would be 1 Hot, 2 Travelers and 1 Neutral.

Mark
 
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