I'm not aware of any that have this, and TBH I doubt that anyone outwith the UK would bother to design such a thing. Most (I think all) of the available granny leads are made outwith the UK. The open PEN fault problem isn't unique to the UK distribution network, but there aren't that many other countries that use PME (off the top of my head, just the UK, parts of New Zealand and parts of Australia, I think). Most of the world uses a different earthing system, either TN-S or TT, so doesn't have a PEN conductor.
The Percerdos granny EVSE as sold by evconnectors.com does a pretty decent job protecting itself imho. I had a faulty car-port which blew up my Rolec ECU via the CP line, but the granny one detected this attempt to feed 240V back up the low-voltage line & shut itself down successfully. The pdf says:
"PERCEDOS is a portable protective system (IC-CPD*) ...<stuff removed>... The device checks the power supply for proper function & only allows current to be drawn from a safe power source. ...
If mains voltage is recognized, the device automatically starts the protective ground monitoring. This monitoring function is constantly active ... and monitors the protective ground connection between PERCEDOS and the outlet for the protective ground wire. ...
The fault current circui breaker additionally protects the user against an electrical accident in case of a system defect. ...
*IC-CPD = In Cable - Residual Current Device for mode 2 charging of electrical road vehicles ..."
Later mentions include:
"In case of detected differential fault current IVn 30 mA, the PERCEDOS®
initially switches off the charging procedure temporarily."
"The PERCEDOS® checks the differential fault current function with
the aid of an internal self-help routine. This self-test is automatically
performed every 4 operating hours, both in active and inactive
operating status. The running of the self-test does not have an
influence on the charging procedure."
and in the specs page:
"disconnection: all poles (L, N, PE)"
"Power connection: L,N, PE/1 phase : L1, L2,PE/1 phase"
next line lists "TN, TNC, TNCS, TT, IT"
"Safety Functions: RCD : PE check of dangerous contatc voltage"
Earth leakage protection (which is what would trip if mains got onto the CP and so back down the CPC) is built-in to every portable charge point in some form or another. That's not at all related to open PEN fault detection, though, as the latter is a specific problem that arises when a PME mains earthing system is used. An RCD or other form of earth leakage device may not detect an open PEN fault at all, as it's quite possible for there to be no current imbalance between line and neutral and yet still have the neutral sat at line potential relative to the local earth potential. As the neutral is connected directly to PE, and the CPC to the installation, at the main fuse, this also means that under these fault conditions any exposed conductive parts that are also connected to the PEN will be at the same potential as the neutral.
The UK opted for PME for two reasons. The main one was that it was cheap, there is a significant cost saving to the distribution network by only having to run two conductors to each property, rather than three. The second reason is that historically (as in 50 or more years ago) earth leakage devices were expensive and also not always reliable. The type in use at the time that we adopted PME was often voltage operated, a VOELCB, and these were costly bits of kit at the time. The electricity boards, that were then government owned and looked after the LV distribution network as well as the sale of electricity to consumers, took the view that they could save money and get rid of all forms of earth leakage device if they adopted PME.
The reason has to do with PME giving a very low earth loop impedance, Ze, no higher than 0.35Ω, compared with the much higher earth electrode resistance, Ra, for a TT installation of typically around 50Ω to 200Ω. This very low earth loop impedance led to the view that a fuse could provide protection if there was a short to PE, not something that will work for a TT installation, as the high current will raise the potential on PE to a dangerous level above local earth in the event of a fault current. It was a happy coincidence for the electricity boards that adopting PME reduced both the cost of installing and maintaining earth leakage devices and also reduced the cabling cost significantly.
The fact that it created an additional risk if the PEN conductor happened to go open circuit was dealt with by mandating that all installations must have big earth bonding conductors, tying all the exposed conductive parts to the same potential. This works fine indoors, where much of the electric shock risk was, as with all the "earthed" stuff tied by conductors to the same potential, even if they did rise to a dangerous voltage the occupants wouldn't be in danger. Needless to say, the cost of the earth bonding didn't fall to the electricity boards, but to the consumer, so was another win for them.
To deal with the risk outdoors, it's always been the case that the risk from an open PEN fault should be considered by the installer. Things like caravan and marina hook up points, hot tub and swimming pool installations, etc, as well as metal framed buildings, have always been considered to pose a risk, and it's been common practice for decades to wire installations like these up as TT, with an earth electrode and RCD. Car charge points are just an extension of this, with the difference that they are being installed by people who may not be familiar with TT installations and may not feel comfortable with installing and testing them. To this end various open PEN fault devices have been created, all of which are less safe than just wiring the installation as TT. The main reason these open PEN devices have suddenly come in to existence is because they are simpler for the installer. The manufacturers have lobbied for the regs to allow these things simply because they don't want the hassle of installers having to fit earth electrodes, even though they would all have to admit that a proper TT installation would be safer.
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