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A very recent book on wiring shows two GFCI protected receptacles wired together in close proximity over a countertop.

I expected the wiring would be:

  • power-in connected to LINE screws on 1st GFCI receptacle
  • cable connected to LOAD screws in 1st GFCI receptacle and runs to 2nd plain receptacle It seems like this protects both. However, the book suggest using two GFCI receptacles wired like this:
  • power-in pigtailed to LINE screws on 1st GFCI receptacle and cable out heading to 2nd GFCI receptacle
  • at 2nd GFCI receptacle, connect the cable to LINE screws.

Why are two GFCI receptacles used instead of one GFCI which protects itself and a second plain receptacle?

I have attached a picture. Please tell me if that violates any copyright laws so I can remove the picture. After studying the picture, I wonder if the answer to my own question is that this wiring allows the circuit to be extended beyond the GFCI receptacles using the same 12/2 cable. double GFCI small appliance circuit

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  • 1
    Just guessing but your way kills power to all the outlets, his way only kills power to that outlet. Will let the experts say what a fool I am.
    – crip659
    Sep 26 at 19:21
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    Show us a picture of the diagram. The NEC requires kitchen countertops to be served by two 20A/120V circuits - which could easily be fed by an MWBC from the breaker and then split up at the GFCI receptacles, each protecting their downstream chains.
    – nobody
    Sep 26 at 20:48
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    If I read the picture right, only the GFCI outlet/device is protected, any outlets(plain or GFI) pass that point/added to circuit would not be GFI protected from the first GFI outlet, they stay hot.
    – crip659
    Sep 26 at 22:18
  • What book is this? Thanks.
    – Sabuncu
    Sep 27 at 11:55
  • The book is 7th edition of Black & Decker The Complete Guide to Wiring (current with 2017-2020 Electrical Codes). The picture is on page 156.
    – Ken Smith
    Sep 27 at 17:41
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Because of the way the book flows its discussion. You're showing us their second "alternate" scenario. Their first "primary" scenario is a Multi-Wire Branch Circuit (MWBC) in which the individual GFCIs would be required due to the shared neutral.

It is showing this as an alteration of that design.

They didn't want to introduce 2 new concepts at once, because it would be more difficult to follow. So here, they introduce the single concept of turning the MWBC into two plain branch circuits.

Now that they've reached this point, they could have another alternate that explains how to use the downline protection system to reduce GFCI count.

Regardless...

Using the downline protection feature of GFCIs isn't always/automatically the right thing to do. There are instances where it's not suitable, such as:

  • users have difficulty locating the reset when it's at another outlet (but that could be taken care of by improving the mandatory "GFCI Protected" labeling to state where the reset is).

  • someone doesn't know what they are doing and would be better off leaving the warning tape on the GFCI "Load" terminals - that applies to a lot of people

  • something downline needs to NOT be on GFCI, such as a refrigerator

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  • I frequently notice all the receps in a commercial rest room are GFCI devices. Presumably they paid the premium for GFCI everywhere so that a trip at one location doesn't cause outage at another location -- even when they're at opposite ends of the same countertop and seldom get used anyway..
    – Greg Hill
    Sep 27 at 5:12
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What the book suggests is overkill. What you said is commonly done: Line in to the GFCI and load to the downstream outlets. You are supposed to put a little sticker on the downstream outlets saying they are GFCI protected, but that's often overlooked.

Yeah, a tripped GFCI would kill power to the downstream outlets, but so what? Just reset it. Just don't put your fridge/freezer on a GFCI outlet (yeah, I know current code calls for it, or at least AFCI), but I still wouldn't do it. My bad, but hey.

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  • Another question answer also said that the code was expecting appliances to be newer than 2014 standards(They not suppose to trip GFCIs so often).
    – crip659
    Sep 26 at 22:06
  • I never put the stickers on. No inspector has ever said a word. It's probably the most common code violation that no one cares about.
    – DrSparks
    Sep 27 at 1:33
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It's a book that was clearly not written by a lifelong electrician or contractor. No contractor would ever make such an installation, simply for cost reasons. There is absolutely no measurable benefit to doing so.

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  • I don't understand why this post got a DV, I UVoted it because I think it's spot on. Sep 27 at 2:44
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    Maybe it was an electrical textbook author. 😂
    – DrSparks
    Sep 27 at 3:41
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    One measurable benefit is that all other outlets keep working and you don't have to hunt around to find out which one tripped if you're in the middle of a task. (not the down-voter).
    – JPhi1618
    Sep 27 at 13:35
  • I should have said. The cost/benefit ratio is not worth it to most people. Most people would not install any GFCIs or they could get away with it.
    – DrSparks
    Sep 27 at 20:04

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