Below is a link to an interesting thread on the Mike Holt electrical forum about whether or not GFCI's work properly as intended and if they're in compliance with UL. This may be of interest to RV-ers as we all have them and they do sometimes cause problems. Perhaps getting a GFCI tester would be a good thing to have.To quote the thread starter "LED indicators, SmartLock technology, internal self testing and the test/reset buttons do not accurately verify that a GFCI is functioning correctly. They do not tell you the speed at which a GFCI will trip, nor do they demonstrate that power has successfully been interrupted once the receptacle has tripped. Plugging in a load does not guarantee it either."Warning - it is 19 pages and nearly 200 posts long.Mike Holt forum GFCI discussionThe thread also points out that there is a revision to UL 943 effective June of last year requiring a self-test function and line-load reversal miswire function. If you are buying a new GFCI receptacle, you might want to check that it complies with the latest UL standard and not just that it says "UL listed". Begs the question - how many RVs purchased after June/2015 have GFCIs that comply with the latest revision? (Installers are permitted to install old stock tho.)I wonder how many 20 amp GFCIs in pedestals could be faulty?

it's probably true that the self test cannot guarantee interuption occurs as fast or faster than it should nor that it absolutely positively 100 percent verifies the circuit interuption. Kinda like you can't absolutely positively guarantee under all possible conditions that a normal breaker is absolutely guaranteed to trip on every overload it should trip on every time.But, when you hit the test button, if the GFI trips when you hit the button, that's very very very likely fast enough to protect you, and if your paranoid, you can always plug in a circuit tester to see it interupted the line.Likelyhood that it won't interupt is very very very small.And if that doesn't satisfy you, just plug in one of the external plug testers with a built in GFI test button and see if it opens the circuit.And if your worried about old std GFI's in the trailer, what about all the old std ones in your sticks and bricks house? Some of the early ones didn't interupt on a ground/neutral short, that was a later addition to the requirements.My experience is that when I've ever had an issue with a GFI it was that it was tripped and couldn't be reset, not the other way around would't trip on a GFI.

How many folks have actually gotten a shock from a non gfci connection?I always treat power cables and cords as if they were live.If I have to connect or disconnect in wet conditions, I wear silicone oven mitts and rubber boots.I prop up any plugs for extension cords so they won't become immersed.Is this so difficult that fast acting gfci is a must do for protection?Last time I got shocked was in 1976 when I was installing a telephone cable and the phone happened to ring just as I was connecting the wires to the lightning suppressor.

pianotuna wrote:How many folks have actually gotten a shock from a non gfci connection?I always treat power cables and cords as if they were live.If I have to connect or disconnect in wet conditions, I wear silicone oven mitts and rubber boots.I prop up any plugs for extension cords so they won't become immersed.Is this so difficult that fast acting gfci is a must do for protection?Last time I got shocked was in 1976 when I was installing a telephone cable and the phone happened to ring just as I was connecting the wires to the lightning suppressor.POTS line tip and ring can get ya. It also kills slugs if they get in the distribution box in the yard and start crawling across the terminals. which then ends up with lots of static on the line. and a mess to clean up.IMHO one of, if not the biggest plus to a GFCI is the protection it provides for little kids and what they may try to do around an outlet. And a GFCI does NOT guarantee protection from a shock. Only works if there is enough leakage current to ground. So...... put on the rubber boots, and get across the hot and neutral. Good chance a GFCI will not trip. If it doesn't see an imbalance of current between the hot and neutral, No trippy!

When I was a kid we had knob and tube wiring and we all lived. When we bought this house it had knob and tube wiring and we all lived. We updated it about 30 years ago and I'm not worried about a new standard.

pianotuna wrote:How many folks have actually gotten a shock from a non gfci connection?I have, and in a situation where frankly I could have been electrocuted had the circumstances been only a little different.I had the sump pump in my basement fail to work properly (which has happened a few times for various reasons) and got an inch or so of water in the basement. As I was picking stuff up off the floor, I picked up an electric drill that I did not realize was still plugged in...and got a jolt. GFCIs are now required in basements, by the current code, but that was not required when my house was constructed. At any rate, standing in bare feet in water with an energized power tool, and/or then picking up said tool, could well lead to electrocution under the wrong circumstances.In my opinion, it would not be a bad thing to have GFCIs on every electric circuit in a house or RV, at least on every circuit that has an outlet or light with a removable bulb. They can and do save lives.

Can you trust the test & reset buttons on a GFCI?

Harvey51
Explorer
Oct 05, 2016
GFCI is supposed to trip at or below 5 ma, so a good test is to stick a 20 k ohm resistor into the outlet from hot to safety ground and see if it trips.

I got my first wee tingle from a GFI standing in water in rubber boots and holding an old sump pump. Just a little tingle before the GFI tripped. I was glad I had plugged it into a GFI outlet. Good device. Too bad they each use $5 of electricity per year now. And arc fault interrupters twice as much.
wa8yxm
Explorer III
Oct 03, 2016
I see a problem with that automatic self test..
(What is it you ask)

Per the article as I read it it means that from time to time the GFCI will, in a manner of speaking, press it's own TEST button, and trip. (one way it can work).

Imagine if that GFCI is feeding a CPAP and you, as a result, do not wake up in the morning.

Or if it's feeding a fridge and by the time you reset it all the food is spoiled.

Or.. Well several other disasters.

Do I trust the buttons? I trust them for the purpose they are designed.. but I play safe when working with Electricity or electric tools. I grew up BEFORE we had GFCI's to protect us.
westend
Explorer
Oct 02, 2016
My Dad gave me my first lesson about electricity. While trying to make functional a string of series powered Christmas lights, he suggested that I put my finger in an open socket, just like I was trying to accomplish. It was a valuable lesson.

BTW, I don't suggest anyone do this as a parenting technique. There are other ways to teach the effects of electricity on the human body.
D_E_Bishop
Explorer
Oct 02, 2016
I haven't had but two or three failures in my career and I feel that they are pretty cool devices. Having one on a circuit in my carpeted house is overkill, having them outside and in wet locations, prudent.

We had some 25 amp made especially for our signal systems and they had surge protection built into the assembly. Overkill maybe but, with 4500 computers in vented aluminum cabinets installed outdoors and protecting folks from exposure to shocks and the computers from all sorts of chip killing situations, cheap insurance.
MEXICOWANDERER
Explorer
Oct 02, 2016
Ordinary Mechanic'c NITRILE GLOVES are excellent protection when working around live circuits. They are inexpensive. Use TALC on the hands to make on and off effortless.
Chuck_thehammer
Explorer
Oct 02, 2016
last hit from electrify, 1988, working on LIVE power amplifier.(needed to). 5,000 volts but little amps... I did not touch, it jumped. then I did.

I learned where and where NOT to put my fingers.

GFCI are to sensitive..my opinion.
MEXICOWANDERER
Explorer
Oct 02, 2016
Does sticking left index finger into "L" Megawatt terminal, count?
drsteve
Explorer
Oct 02, 2016
pianotuna wrote:
How many folks have actually gotten a shock from a non gfci connection?

(raises hand) More times than I can count.
DrewE
Explorer II
Oct 02, 2016
drsteve wrote:
DrewE wrote:
In my opinion, it would not be a bad thing to have GFCIs on every electric circuit in a house or RV, at least on every circuit that has an outlet or light with a removable bulb. They can and do save lives.

No argument that they are a good safety device, especially in wet areas, but the NEC does not require GFCI protection on overhead lighting circuits. You wouldn't want to be left in the dark by a random trip of the sort GFCIs are famous for.

RV lighting is 12VDC so GFCIs don't apply.

Indeed the code does not require GFCIs for many circuits, and I didn't mean to suggest thag. AFCIs, a somewhat different beast, are now required and from what I have read more prone to falsely tripping. In my (limited) experience, GFCIs are not overly prone to false trips, but ground faults can be devilishly tricky to track down.

(AFCIs are arc fault circuit interruptors and attempt to stop sparking loose connections and similar problems. Telling sparking motor brushes from sparking loose wjre nuts doesn't always work.)
drsteve
Explorer
Oct 02, 2016
DrewE wrote:
In my opinion, it would not be a bad thing to have GFCIs on every electric circuit in a house or RV, at least on every circuit that has an outlet or light with a removable bulb. They can and do save lives.

No argument that they are a good safety device, especially in wet areas, but the NEC does not require GFCI protection on overhead lighting circuits. You wouldn't want to be left in the dark by a random trip of the sort GFCIs are famous for.

RV lighting is 12VDC so GFCIs don't apply.

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