So I finally got around to putting GFCI outlets in the Kitchen – moved in last year, there was an outlet right over the sink without GFCI – and I’m having trouble with one circuit.
I have three outlets on the Kitchen island, wired in series. Two are on the counter, and one is underneath for the phone. I originally put a GFCI on the first outlet in the series, nearest to the sink; when I then tried to put the second outlet on the load portion of the GFCI it tripped it without fail; checked all the connections, still tripped it; I finally ended up giving up and wiring both to the Line terminal; so first outlet is protected, (luckily one near the sink) and the other two are not protected.
Later, I put GFCI outlets on the three countertop outlets – each one is on a different circuit. Two are in mid-circuit – so, I tested which side was hot after pulling the old outlets, wired this side to the Line, and the other side to the load (I’m actually having second thoughts about one outlet, because it feeds the dishwasher – probably will leave this off the GFCI by wiring both to Line again). One circuit works fine, the other one trips the GFCI every time. Checked the wiring – OK, line and load are properly connected, ground is OK, if you take off the load wires, the thing works fine, but trips with them on. Come to find out that the circuit then feeds the island countertop GFCI – so the same circuit seems to be tripping this GFCI further upstream!
Question – can you have two GFCIs in series? I know it doesn’t make any sense to, but will it work?
Is there something wrong with this circuit? Should I investigate it further? Not looking forward to this option as circuit is buried deep in the island and I don’t want to disassemble it.
Code now says GFCI on all outlets on an island, no? So should I put yet a THIRD GFCI on the same circuit so that all countertop outlets are protected (last outlet is probably 9 feet from the sink).
Any suggestions/replies greatly appreciated,
Ben
Replies
The first thing to be clear on is that house wiring is never done in series, it's parallel.
Any chance of a diagram? I'm having a hard time following your description.
I suppose that wiring is "parallel," in the sense that all outlets are between a common hot and neutral.
Here is my diagram for the kitchen island - I now also have a GFCI further upstream (where PANEL is in the diagram, wired as in the second circuit).
Keep in mind that, once the wires leave the "load" side of the GFCI, NEITHER wire can "cross-connect" with any other wire. Sometimes the downsteam neutral wires are cross-connected, and sometimes a shared neutral is used when two appliance circuits are drawn off of a double breaker.
No shared neutral wire - no appliances on the circuit.
Sorry, ? what does "cross-connect," mean? There is just two more outlets in series.
Cross-connected simply means that you've got a wire from one circuit tied to a wire from another circuit (or from the same circuit but the other side of the GFCI).
In older wiring styles it wouldn't be uncommon for all the neutrals coming into a box to be tied together, even though they were on two different circuits. (And it still happens in newer wiring when someone doesn't know what they're doing.) And it's not that unusual to find two hots that have been tied together somehow.
And of course, if a neutral is tied to a ground, that will cause the GFCI to trip too.
I can't see anything wrong with your diagram, so there must be some other factor. Perhaps a neutral is touching a ground somewhere, or as Dan suggests, there may be another circuit connected.
Anything that would cause the slightest imbalance of current between the hot and neutral will trip ia GFCI.
Try a new GFI maybe you got a bad one. It happens.
Is your wiring NM (Romex)?
If the cables connect to boxes using metal screw-down NM connectors or metal screw-down clamps in the box, it is possible that the connectors are over-tightened, causing slight bleed off of current from, say the neutral to ground. All it takes is for the GFCI to see a few milliamps of difference between hot and neutral to trip. I believe that overly tight staples can do the same.
That's happened to me a few times!