Stange Problem with GFCI

[denelec]

I've never seen a meter with anything but a solid link for a neutral, so I'd love to know how that's meant to work..

Don't know.  Maybe old meters measured both the line and return current in the neutral?
Our meters don't measure the neutral current or line to neutral voltage.  Only the 2 line currents and the line to line voltage.
A line to earth load would appear the same as a line to neutral to our meters.
But I doubt that a modern meter would be blind to a line to earth load.

[Monkeh]

But I doubt that a modern meter would be blind to a line to earth load.

Neutral and earth in my house only diverge a few inches ahead of the meter. It would neither know nor care if I returned all load current via 'earth'.

[denelec]

But I doubt that a modern meter would be blind to a line to earth load.

Neutral and earth in my house only diverge a few inches ahead of the meter. It would neither know nor care if I returned all load current via 'earth'.

Yes. But what if you used another earth reference not physically connected to your electric panel such as a ground rod?

[Monkeh]

But I doubt that a modern meter would be blind to a line to earth load.

Neutral and earth in my house only diverge a few inches ahead of the meter. It would neither know nor care if I returned all load current via 'earth'.

Yes. But what if you used another earth reference not physically connected to your electric panel such as a ground rod?

Then the current would find its way through the earth to another rod connected to the PEN..

[denelec]

Then the current would find its way through the earth to another rod connected to the PEN..

You meter shouldn't see any difference unless it somehow monitored both the line and neutral currents.
We need an expert on old European meters...

[Monkeh]

Then the current would find its way through the earth to another rod connected to the PEN..

You meter shouldn't see any difference unless it somehow monitored both the line and neutral currents.

That's what  I said several posts ago... It, like every other single-phase meter I've looked at, has a solid link for neutral. It does not care whether load current passes through it or not.

[denelec]

That's what  I said several posts ago... It, like every other single-phase meter I've looked at, has a solid link for neutral. It does not care whether load current passes through it or not.

If you used one of our meter in your house, a 100W line to earth load would appear to it as 50W.
That's because a 120V load produce a current in only one line and a 240V load produce a current in both lines in our system.
Since our meters have no ground or neutral connection, L1 would be 240V and L2 would be neutral in your setup.
So both line and neutral current would be measured.
Maybe your old electromechanical meters were made like ours.

[Monkeh]

That's what  I said several posts ago... It, like every other single-phase meter I've looked at, has a solid link for neutral. It does not care whether load current passes through it or not.

If you used one of our meter in your house, a 100W line to earth load would appear to it as 50W.
That's because a 120V load produce a current in only one line and a 240V load produce a current in both lines in our system.
Since our meters have no ground or neutral connection, L1 would be 240V and L2 would be neutral in your setup.
So both line and neutral current would be measured.
Maybe your old electromechanical meters were made like ours.

We're not talking about your split-phase system. It has never been used here, we have never used a meter like that.

[SeanB]

Electricity thieves use a SWER system, as a single cable is easy to install and hide. Thus a ground return will show up as a fault.

[madires]

The common meter in Germany is a Ferraris type for 3 phases. It's connected to neutral, which is connected to the building's grounding system. Therefore the meter would also count any "stolen" power. RCDs were introduced to prevent electric shocks and not for detecting power theft.

[Terabyte2007]

Swapped the little bugger out last night. Here is the culprit. I will do a short teardown on this guy over the weekend. It's a Leviton with a 92 date code.

Also, this is a 20 Amp GFCI, can anyone spot the major difference to modern GFCI's??? Or even outlets?

[NiHaoMike]

A proper 20A outlet has that extra sideways slot. However, for some reason, it only seems to appear in commercial buildings.

[Richard Crowley]

The "sideways" slot implies that the full 20A is available from that outlet. It is very rare in a domestic situation to provide a branch circuit with a single outlet, typically there are  many outlets on a circuit. So even though the circuit may be 20A, you can't be assured that you are the only load, so those 20A outlets are inappropriate.

At least that is how mains wiring is done in North America. In UK, they have "ring" circuits with individually-fused outlets plugs. Dunno what they do down there in OZ?

Updated per correction from Monkeh.  Thanks!

[Monkeh]

At least that is how mains wiring is done in North America. In UK, they have "ring" circuits with individually-fused outlets.

Individually fused plugs.

Dunno what they do down there in OZ?

Normal single-phase radials.

[Terabyte2007]

Ok, folks. Here is the teardown pictures. I am sorry I did not have time to do a video teardown of this GFCI, but projects at work were keeping me busy.

Interesting find, the plastic outside plug case says that this GFCI is a 20 Amp but the stamp on the internal framework states 15 Amp, What's up Leviton?

BTW, the small bar with a resistor tacked to the end was the test button. This would actuate the protection circuit. Also, can anyone tell me what the RA9031A 8 pin IC is? I could not find the data sheet on this.

[SeanB]

Interesting that yours is mains powered. The ones used here are all powered by the imbalance current.Older ones ( late 1960's to early 1970's) used a BRY39 GCS thyristor to drive the trip relay, while the later ones up to the current generation use a simple biased coi to operate the trip mechanism, the trip drive energy being stored in a spring. They will operate with overvoltage, undervoltage and even with a broken connection to neutral on the supply side. There were a small range that had overvoltage and phase reversal protection, which used a 275V varistor on the line side and a 100v varistor on the neutral side, with the common along with the test resistor being connected to an earthing wire. There was also a range of prepayment meters which used the basic trip mechanism as a disconnector for the power, and they were quite common though they had a flaw in that you dould disable the trip by putting a needle into the unit through the plastic label they placed over the hole where the test switch was. Later on they put a plate there to block this hack. Newer meters also have back end checks as the payment is linked to the meter number, the old ones were a prepaid number that worked on any meter.