Replacing GFCI / residual current interrupter

Good find!

If yours passes the self-test, I would not bother to replace it. Be sure to test it every time you connect to shore power, however.

Also, any DIN-rail RCD should work, as long as the trip current is 0.03A and the overall capacity is as high as you'll be using ... i.e., much less than 30A if you are not using the roof air conditioning.

I too am pessimistic about Airstream or Westfalia helping out at all. The rationale is as follows. If you look at all the things they had to change or completely re-engineer for the NAFTA version: (non-exhaustive list off the top of my head)

- LPG storage
- Roof air conditioning (two versions)
- Water heater
- Black tank and under-floor plumbing, "poop chute"
- Hob / sink (see the labels; ours is a USA-specific unit, not sure how exactly)
- Extractor fan and heat shield
- Skylight remote (USA-only redesign, or global?)
- Generator
- Battery charger
- Front seat belts
- Drain traps and sewer vent
- Graphics
- TV and phone hookup
- RVIA certification and various stickers

Combining this with the fact that transaction prices in the USA on units with almost all options were less in Dollars than the suggested retail of base vehicles in Euros, it's likely that Westfalia and Airstream lost big money on the whole project. It's too bad, and there are a lot of reasons for it that would make for another thread, but long story short, it seems to me that in hindsight Westfalia and Airstream wish it had never happened!

We're just all lucky to be part of this tiny group!

Ted

I found a PDF that describes in detail the functionality of the RCD:

http://www.alliedelec.com/images/products/datasheets/bm/ABB/70241938.pdf

I think it is important to point out that an RCD is a device intended to protect equipment.
Whereas a GFI is intended to protect people.
They seem to operate in a similar fashion - IE: detect leakage to ground.
However - the GFI trips at 5ma whereas an RFD trips at 30ma.

Reading a little further at this website suggests 5ma is an appropriate threshold.

http://www.bassengineering.com/e_effect.htm

Ventricular fibrillation can occur at current levels as low as 30 milliamps for a two year old child.

The Allied Elec website even describes this as a device intended for equipment protection:

ABB
Circuit Breaker; GFEP Ground Fault Equipment Protection; 2 Pole; AC; 25A; 30mA


...

In truth there are other variables that sway my opinion about replacing the defective RCD in my Westy. I don't normally like to go into so much detail as to bore people. However - there is nothing boring about being electrocuted!

When this issue first surfaced I was under the assumption that we had a GFCI device in our Westys. If you look at the breaker panel circuit labels it clearly states GFCI. But when you research the device further you realize it's an RCD - which is something different. The deeper you dig the more differences you find.
1) RCD is a passive device whereas GFI is an active device - IE: has a circuit board
2) Questions about which devices protect against which scenarios
a) leakage between hot and neutral
b) leakage between hot and ground
c) leakage between neutral and ground
3) RCD trips at 30ma vs GFI trips at 5ma
4) "A" version of RCD offers protection in both AC and pulsating DC
5) "AC" version of RCD only offers protection in AC circuits
6) RCD's are common in Europe whereas GFI's are common in the US
7) European line voltage is 220 Volt @ 50 Hertz
8) How does a European RCD device rated for 220 Volt operate in a 110 Volt circuit?

Having worked as an RV technician for some years I know that the AC wiring in an American RV is different from typical household wiring. In a house AC neutral is typically 'bonded' to earth ground. In a typical American RV this is not the case. Your typical RV does not have an earth ground to bond to. It's sitting on rubber tires... So Iv'e always wondered how can a GFCI device that is designed for household wiring work the same in an RV? And of course you encounter some nuances when comparing the difference between running on generator vs shore power. At the pedestal AC neutral is bonded to earth ground. So when you plug into shore power does that mean the chassis of your rig has one leg of AC current pulsing through it? And if so under what conditions can you test positive for 'hot skin'? And what if the shade tree mechanic who wired up the pedestal in the RV park got his wires crossed? Iv'e seen it happen!

Suppose you decide to install an inverter in your rig or a previous owner already did. How is it wired into the existing AC circuits? Is the inverter ground bonded to the chassis? Is it a true sine wave inverter? If it's a higher wattage low cost inverter it probably produces a modified sine wave. Which is basically just a bunch of square waves. Which is basically just pulsating DC. In which case the less expensive "AC" version of an RCD might not provide any protection at all.

At one point most of our Westy's had their Air Conditioner upgraded to a higher output cooling unit. Subsequently they supposedly installed a higher current circuit breaker. Did someone miss wire something during that process that rendered our RCD less effective?

Maybe our RCD's still work - perhaps it's just the test circuit that is defective. Or maybe they still work but they trip at a higher current than the test circuit simulates?

The research I performed was not exhaustive - I was left with questions about which scenarios an RCD vs GFI protect people under various circumstances. IE:
1) chassis to hot
2) hot to neutral
3) neutral to chassis
etc...

And of course there is the question of resistance. It varies from one individual to the next. It's generally between 1000 and 2000 ohms. And it varies depending on whether your hands are dry or wet.

Does an RCD offer some protection? Yes! If your hand to hand resistance falls into the average category then ohm's law says you'll probably have enough current flowing through you to trip the RCD.

ohm's law: E over IR
120 volts / 1000 ohms = 120ma
120 volts / 2000 ohms = 60ma
120 volts / 3000 ohms = 40ma
120 volts / 4000 ohms = 30ma

But what if you're standing outside the van with an AC appliance or lying under the van with a drop light and you complete a circuit between earth ground and the van?

There are so many possible scenarios and variables that it's almost impossible to figure out what might happen.

On top of all that I'm just getting tired of fixing all the things that were not done right in the first place in/on/around my Westy.

So Iv'e decided not to invest my time/energy/money in replacing my alleged defective RCD because I don't know what advantage if any I might gain by it. There are just too many variables...

That's my 202 cents worth

John...

Re: Replacing GFCI ABB contact info for recall

Contact chas.l.harris@us.abb.com at ABB, he is the guy my local reps worked though. They wanted me to send in the defective breaker with a RMA, but it took literally months to get the new one in hand. Knowing what I know now I would buy one off eBay.

If you replace it be advised that the GFCI and the 3 breakers to the right share a bus bar you must remove. the GFCI can then be removed by pulling down a small tab in the center back of the GFCI. (you can't easily see it). The new GFCI does not have a notch for the bus bar. shorten the bus bar and use a short piece of 8 gauge wire between the GFCI and the breakers and bus bar. Have an electrician do it if you are not familiar with wiring.

Rob

I replaced my friend's GFCI because the old one would not trip when pressing the test button. I cut the bus bar, added a wire, and hooked up the rest of the wires the way it was on the old one. The problem is that it would still not trip when testing the button. I plugged in a LED circuit and GFI tester, and it showed that the hot and neutral were reversed. I also tried tripping the GFCI by using the button on the tester, but I couldn't get it to trip. So next I switched the yellow and black wires going into the top of the GFCI. The LED circuit tester showed that the wiring was okay, but the test button still won't trip the circuit. I also tried pushing the test button on the new GFCI after switching the wires, and it also still will not trip.

Have I wired this wrong? The attached photo is the new GFCI with the latest wiring attempt. Can someone take a look at theirs and tell me how this should be wired?

Matt

Matt416 said:

... I also tried pushing the test button on the new GFCI after switching the wires, and it also still will not trip.

...

Matt

Click to expand...

A relatively simple test.

Use a 6 watt - 60 watt light bulb as a ground fault test. Most any lamp wattage is fine. Clips or simple twisted wires can be used on a lamp cord plug. Connect one side solidly to ground. I would use the green ground bar (lower left in the picture). Touch the other wire to the output terminal (line/hot) of the GFI. The GFI should trip.

If the lamp lights and the breaker doesn't trip the GFI is defective, or you don't have a proper system ground, or some other issue. If it trips, you need to check further to verify the test circuit operation.

FYI. The integral GFI test button doesn't shouldn't need any ground connection to function. The little polarity light units with a GFI test function do require a ground circuit to perform a GFI test. Those little polarity testers will not properly test a GFI if the green ground isn't working properly.

vic

Is it possibly wired upside down? ie you have input to the top but should it be to the bottom?

Just asking... or does it not matter over on your side of the pond

Keith.

Cheyenne said:

Is it possibly wired upside down? ie you have input to the top but should it be to the bottom?

Just asking... or does it not matter over on your side of the pond

Keith.

Click to expand...

Good observation.

I ass-u-me'd that the black rubber covered cord is the supply from the pedestal/power source. That associated wire appears to be fairly heavy gauge.

If that black cord isn't the supply then it would be worth investigating.

vic

Thank you Aqua Puttana and Cheyenne. Sorry I took a while to get back to this--here is what I found: I used a small light bulb and connected it between the green ground bar and the lower left output of the GFI. It lit up and did not trip the GFI. But more interestingly, I tried the test bulb and it did not light up between the green ground bar and any of the breakers to the right (as you face the box). I then started testing everything with a voltage meter, and there was 0 voltage between the ground bar and the three breakers to the right of the GFI. Also no voltage between the green ground bar and the upper right and lower right of the GFI. When I tested the voltage between the neutral bar and the breakers to the right, it showed full voltage. It also showed full voltage between the upper right and lower right of the GFI and the neutral bar. It showed no voltage between the upper left and the lower left of the GFI. Now, remembering my house electrical, the ground and neutral should be connected, closest to the source. I'm not sure how it works in a motorhome.

Cheyenne-- The GFI is wired the same way as the old one was (of course that doesn't mean it was correct before since the old one didn't trip). The power source comes in at the bottom left of the primary breaker, then goes out the top and to the upper left of the GFI. The red jumper on the bottom I added because the new GFI would not allow the hot bus bar to be connected to the breakers to the right.

It definitely looks like I have a ground problem, since the neutral and the ground are not connected. But before I dive into that, does it look like the GFI is hooked up correctly?

Matt416 said:

... Now, remembering my house electrical, the ground and neutral should be connected, closest to the source. I'm not sure how it works in a motorhome.

...

Click to expand...

With the exception of a generator or inverter supply (special design) the RV vehicle A/C system should keep the ground (green) and neutral (white) wires separated. The neutral ground bond is established only at the main shore service supply. The RV is treated like a sub panel. (Sub panels do not have a neutral ground bond. That is reserved for the main service panel.)

That said, with the 30 amp shore power cord plugged in and powered, the neutral should have the ground bond carried through. When the 30 amp cord is disconnected the ground and neutral should be electrically isolated aka separate (with the possible exception of an included on-board generator or inverter supply grounding method relay or switch).

FWIW. vic

Hi Aqua Puttana-- In the past I have been checking everything with the onboard generator running, but today I tried running it off of shore power and nothing changed (ground and neutral are still separate). I'm still not sure if I have wired the GFI correctly. The top two wires going into the old GFI were switched (yellow on the left and black on the right) and my plug-in tester told me that the hot and neutral were reversed. So I switched the top two wires in the new GFI (as in the current photo, attached). Do you (or anyone else) have an idea of how this is supposed to be wired? Does anyone have a photo of a similar set up?

Matt

Not that this is of much consolation, but ours does not trip when pressing the test button either.....