EV charging on GFCI

The car is grounded through the EVSE. This is why you are not allowed to play with sharp objects. You want to try all manner of things, rather than learning about something first.

Yes, this is one way.

Who knows what other ways they are doing.

Yes, I mean grounding the J1772 plug side of the EVSE, rather than the power side of the EVSE.

So, i am allowed to play with HV, which is not sharp.

It's been a long time since I heard of it, but a colleague of mine had the issue on US mains fed systems feeding inverter drives. AFAIR it was due to the y capacitor in the drive that was not symmetrical, so when the inrush control fed current into the DC link capacitor, it would charge the y capacitors unsymmetric depending on where the turn on was done on the mains curve.

I guess, some GFCIs can be tripped by high differential inrush currents if the DMRR is not perfect (Differential Mode Rejection Ratio, first time I used that term)

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That is the essence, but it's a bit more complex than that. A GFCI detects a difference (of about 5ma or more) in current between the line conductor and the neutral conductor as you described. It also can detect a neutral to ground short on the load side, if one exists. See page 6 of the datasheet:

I don't know if that applies to all GFCI's - I suspect it does. And I don't know if is a factor in the EV charging problem discussed in the thread.

Ed

I'm aware of a similar situation.

Using Pentair pool pumps requires using one and only one brand of GFI breaker. I believe it's a Siemons; I know Square-D's will keep tripping.

I have dug around for a long time, looking for an answer about the cause of this problem and I have yet to find one. The worst sources seem to be the people who install them. One electrician has a document on his web site, where he claims 60% of such devices will fail when used in tandem. That seems rather high, given that the vast majority of EVSEs installed to an outlet, will have such a double GFCI. If it were true that they fail in 60% of installations, this would be a more widely known issue, with a well known solution.

I found a discussion on a Tesla forum where is it claimed that replacing the upstream GFCI virtually always fixes the problem.

I would not be inclined to forego the GFCI on any receptacle. It saves lives. That's why it's in the NEMA code. They continue to look at how people are injured and die, and find ways to prevent those deaths. Some people think they know better, so are happy to ignore what the experts say. It will be too bad, when Ed fries himself, and there is no video of it.

Is it made in China or some other exotic places ? They all know how to seal units so that the user can not check how bad the circuit is :-)

What is the tripping current for the in-house GFCI ? 5 mA or 30 mA ?

If the charger was originally designed for 30 mA GFCI, the mains EMC filters might have too large capacitors from L to PE and thus the leakage is too large.

It is also possible that the manufacturer did not pass the EMC test and simply added the capacitor values to pass the test. Passing the test without tripping the GFCI might mean that an inductor or two had to be added to the mains filter, but that might be too expensive :-).

Why would the GFCI leak ?

Does it have a "TEST" button ? Pressing this button will connect a largish resistor from L to PE and trip the charger GFCI. If pressing the in-house GFCI but not the charger GFCI, the in-house GFCI is more sensitive (5 mA?) than the charger GFCI (30 mA?).

If you have a 100 nF Y-capacitor (L to PE), on 60 Hz it has a reactance of 27 kohm. Applying 120 V to it and 4.5 mA will flow. If the GFCI nominally trips at 5 mA but consider tolerances in the trip current, capacitance, voltage etc. I would not be surprised if the GFCI sometimes works and sometimes trips.

I know that 100 nF is too big for a Y-capacitor and few manufacturers make this big Y-capacitors, but who knows if the charger manufacturer has put multiple smaller in parallel between L and PE :-) to get the EMC values approved.

inverter drives sometime have quite few conditions for use with an RCD

page 28,

"Lasse Langwadt Christensen" snipped-for-privacy@fonz.dk schrieb im Newsbeitrag news: snipped-for-privacy@googlegroups.com...

In our part of EU, ground fault detection has been mandatory for decades. Nowadays, requirements are evolving because users connect new types of loads&equipment to the mains.

There are different types of RCD depending on which kind of fault current they detect (also in historical order): Type AC: only detects AC currents, not allowed anymore Type A: also detects pulsed DC; commonly used now, works for most loads Type F: increased frequency range, seldom use, for inverter drives Type B: trips on pure DC currents, too; required for most inverters and EV charging (needed because fault current could be from EV DC voltage) DC current can also prevent correct funtion of the other RCD types by saturating their coil.

To guarantee correct operation when cascading RCDs, there are a couple of rules. They result in RCDs with different trip levels, delayed versions and special RCD with low DC trip levels (to make sure upstream RCDs still work).

The NEC is not actually a regulation. Each state decides on their own regulations, usually adopting the NEC, but on their own timetable. It's not unusual for a state to wait 20 years to adopt any particular section of NEC. They also modify the language when they choose.

If you say so. The point is, having an NEC section, does not make it a regulation in any state. And states do have their own regulations which can be the same as NEC or can be different. There is no federal mandate to adopt anything in the NEC. NEC is a private organization, not a government body.

Notice some states don't mandate anything. The leave it to the local jurisdictions.

I am sure N is not tied to PE. The EVSE/charger works for 220V also, so both wires are L and no N. The original connector is NEMA-20P, with adapter to regular 110V.

Sorry, 6-20P. with the right pin sideway.

Which code, NEC or state? I'm pretty sure the insurance companies are not going to refuse to insure every building in the state because there is no mandate to use the most current NEC. At this point you are just blowing smoke. Please stop.

Ok, we are off in fantasy land now. This is a simple matter. I gave you links that show what revisions, if any, of the NEC are used in various states. Yes, buildings must be in compliance with the regulations of the state they are in. That's it. NEC is only enforced if the state mandates it. You need to stop BSing now.

Wrong. There are four states that leave it up to the local jurisdictions. Also, each state has selected the revision of the NEC, with some being as old as 2008.

You only need to look at the map and other information provided! But that's too hard for you, isn't it?

Except there is no state code in four US states. Arizona, Illinois, Mississippi, and Missouri.

Only 25 states have adopted the 2020 NEC.

Please stop lying about this.

Yup. That's your MO when you are shown to be wrong. I hope you don't continue spreading wrong information, now that you've been shown the truth.

The NEC is not mandatory in any way. The various jurisdictions adopt the NEC as they see fit, when they see fit. I have provided links, including links at NEC that tell you about this. You don't need to take my word for any of it. But... you are afraid to read, you might learn something.

Not sure what you mean, it's "not a code issue". Why would it be a "code issue"? The code for any jurisdiction is set by that jurisdiction.

You can't seem to understand anything I provide. There's no mandatory adoption of the NEC by any jurisdiction, states, or local. It is for each body to decide. You know this by now, unless you have refused to read any of the links I've provided.

I guess some people are just hard headed. Whatever. We've done this dance before where I provide you with evidence and you refuse to acknowledge that it exists. Hurrah for you!

If you read the information on the map and web page, you will see that states can modify the NEC language. But that would require that you actually read the page and make some attempt to understand that you might not be right!

And yet, the quoted material does not say that. You are inserting your meaning into the tiny bit of language you found.

You are being a BS artist. If a state does not require building to some provision of the NEC, the builders will not be building to that provision and the inspectors won't be inspecting to that provision. This means the insurance companies will have no way to determine if a building conforms to a provision of the NEC that is not required in that state.

You are full of hot air. You can't find anything to support your claims, so you twist things to claim they say what you are saying. Why are you like this?

Meanwhile, you are distracting from all the other parts of this discussion I have proven you wrong about.

Lol, Darwin award :-)

Most switchers have leakage to ground, due to the input filters, but all such loads should have a 3 wire input with protective earth. If the trip is going, then it's detecting an unbalanced load per wire, perhaps not uncommon with smps, due to possible input filter imbalance.

Line is 240 volts here and would never use a two wire supply for any appliance, unless double insulated. Why not use the house heating / stove outlet, which should have a protective earth ?...