Backward wired GFI

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hillbilly

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A customer had a problem on 4 outdoor receptacles.

Seems the GFI receptacle was "hot", but the other (3) downstream receptacles were dead.

The problem had existed since the home was built (4 years), and he was tired of having to go to this one GFI receptacle to get power for outside.

He had another "electrician" look at it, and he couldn't find the problem.:confused:

The first thing that I noticed was that the test button on the GFI wouldn't work....no trip or re-set function, although the receptacle was energized.
This is a newer GFI, so I was pretty sure that something was wired wrong.

I pulled the wires out of the receptacle and used my voltage detector to locate the un-grounded (hot) conductor.
The problem turned out to be that the receptacle was wired backwards.
The line conductors were installed in the "load" terminals and vice versa.

I was suprised, I didn't know that a GFI could be fed "backwards" and have power on the outlet (plug-in) terminals.
The "line" wire terminals on the GFI weren't energized, hence the "dead" downstream receptacles.

I found another GFI receptacle in his basement that was wired the same way.

I learned something new.

steve
 
hillbilly said:
The problem turned out to be that the receptacle was wired backwards.
The line conductors were installed in the "load" terminals and vice versa.

I was suprised, I didn't know that a GFI could be fed "backwards" and have power on the outlet (plug-in) terminals.


I learned something new.

steve
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Good for you Steve. Now keep quite about it. This is considered esoteric knowledge even though it's written on the installation instructions. If people ever start to read the instructions it will really put a dent in the income of the service electrician. I find a least one or two a week.

By the way I'm just joking ( no matter how many times you tell homeowners and maintenance people about this they still manage to wire them backward ). :grin:
 
growler said:
By the way I'm just joking ( no matter how many times you tell homeowners and maintenance people about this they still manage to wire them backward ). :grin:
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Step #1, remove that irritating yellow sticker that covers the load side terminals...:D
 
hillbilly said:
This is a newer GFI, so I was pretty sure that something was wired wrong.
Click to expand...
Today they ship from the factory already tripped, and the reset button won't work if it is wired backwards anyway.

I thought this feature had been in place for more than 4 or 5 years now... Anyone know how long that has been the case?
 
growler said:
Good for you Steve. Now keep quite about it. This is considered esoteric knowledge even though it's written on the installation instructions. If people ever start to read the instructions it will really put a dent in the income of the service electrician. I find a least one or two a week.

By the way I'm just joking ( no matter how many times you tell homeowners and maintenance people about this they still manage to wire them backward ). :grin:
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How about the call about the recp. in the half bath has no power, quick check in the master bath and the customer now knows what that "little button" is for $$$$
 
The newer GFCI receptacles shouldn't work at all if they're mis-wired. This requirement I believe came from UL and had been around for a few years.
 
infinity said:
The newer GFCI receptacles shouldn't work at all if they're mis-wired. This requirement I believe came from UL and had been around for a few years.
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Mike holt news letter, they were required to stop making the old type GFCI on July 28, 2006. They may still be selling them because I changed out three last friday. This was a motel chain and the old GFCI's may have been in the supply chain for years but they were recently installed.

http://www.mikeholt.com/newsletters.php?action=display&letterID=148
 
growler said:
Mike holt news letter, they were required to stop making the old type GFCI on July 28, 2006. They may still be selling them because I changed out three last friday. This was a motel chain and the old GFCI's may have been in the supply chain for years but they were recently installed.

http://www.mikeholt.com/newsletters.php?action=display&letterID=148
Click to expand...


Thanks for the link. I knew that I read this information somewhere:

Reverse Line-Load Miswire: a GFCI will deny power to the receptacle face if it is miswired.
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If the receptacle is wired backwards, but still had power to it, is it possible the power was also wired into the wrong set of terminals?

That would explain the no trip or reset function even though the receptacle was energized. If you wire to the wrong terminals you are basically backfeeding the receptacle.

It would be just like backfeeding a panelboard with the main breaker tripped. The bus would still be hot.

Steve
 
Who was the first "electrician" who could not figure that out???? Talk about no qualified people.....Don't forget the "company" who wired the house in the first place. I guess they don't do final check outs..... Do the kit receps work????
 
steve66 said:
If the receptacle is wired backwards, but still had power to it, is it possible the power was also wired into the wrong set of terminals?

That would explain the no trip or reset function even though the receptacle was energized. If you wire to the wrong terminals you are basically backfeeding the receptacle.
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See posts #4 & #6.

GFCIs are no longer manufactured to allow that to be the case. They arrive from the factory "tripped" and will only reset if the line side ungrounded & grounded terminals are connected properly.
 
I always wondered why they put the sticker on the back of a faceless gfi it is not like you can put a faceless in and not have to pull the sticker off
 
splinetto said:
I always wondered why they put the sticker on the back of a faceless gfi it is not like you can put a faceless in and not have to pull the sticker off
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To make sure you actually pay attention to which is LINE and LOAD would be my guess...
 
splinetto said:
I always wondered why they put the sticker on the back of a faceless gfi it is not like you can put a faceless in and not have to pull the sticker off
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Maybe 'cause they're using the same manufacturing process, just with different parts? Once they're assembled, down the line they go, and it's cheaper to just let the machine slap a sticker on it than turn it off for the production run, then back on for regular GFIs.
 
tallguy said:
See posts #4 & #6.

GFCIs are no longer manufactured to allow that to be the case. They arrive from the factory "tripped" and will only reset if the line side ungrounded & grounded terminals are connected properly.
Click to expand...

Sorry, I for some reason, thought the original post said the hot and neutral were switched. After reading it again, he did say that the line and load were reversed.

I just checked the P&S website. The specification grade receptacles say this:

Prevents line-load reversal miswire: no power to the face or downstream receptacles if wired incorrectly.

The Trademaster grade receptacles say this:

Prevents line-load reversal miswire: If miswired, GFCI cannot be RESET.

Looks like on the trademaster, you still get power to the face even though the receptacle won't reset.

Steve
 
On older GFI units, it was possible to reverse feed them, but the protection was only available on the downstream outlets. :mad: That scenerio is no longer possible with the newer units.

We recently connected a new modular home that had the supposedly "new" type of GFCI receptacles installed. During our initial walk-thru after the power had been switched on, we discovered something unusual:

There was this GFI outlet in the kitchen with the green light lit, and I pressed the test switch on it.

~POOF~

Now the GFI would not reset. :-?

Upon investigation, we determined that the GFI was wired backwards, with the incoming line connected to the load terminals. Since it was already "set" before being energized, it did provide power to the face and the downstream outlets, but once it was tripped out, you could not reset it.

Reversing the lines on the device solved the problem.:cool:
 
steve66 said:
The Trademaster grade receptacles say this:

Prevents line-load reversal miswire: If miswired, GFCI cannot be RESET.

Looks like on the trademaster, you still get power to the face even though the receptacle won't reset.

Steve
Click to expand...



GFCI receptacles are shipped from the manufacturer in the tripped position so you couldn't get power to the face if you can't reset it.
 
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