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The TLDR is EV chargers want an exemption from ground fault protection because they have ground fault protection built in. Lots of devices have built in protect

by mike_d 2y ago

The TLDR is EV chargers want an exemption from ground fault protection because they have ground fault protection built in. Lots of devices have built in protections for various electrical faults, but we still put them upstream because one of the things we are protecting against is the device itself faulting. It is like the people holding this view don't understand that Wish.com and Aliexpress exist.

pkulak 2y ago
So then what’s protecting the protection? And that protection? At some point you have to stop. EVSEs have to be UL rated and conform to the J1772 spec. Their entire reason for existing is safety, and they basically don’t do anything else. They don’t modify the delivered power in any way. I guess they have a plug that’s rated for 1000s of connection cycles, but that’s really a safety thing too. Putting another GFCI behind that is a silly waste of time, money and another point of failure.
- mike_d 2y ago
  > So then what’s protecting the protection? Look out your window at the power pole, you'll see a transformer. That has breakers, differential relays, and other protections. > And that protection? Substations have RTUs and SCADA systems that are constantly monitoring everything for faults. They have cool shit like oil breakers that can kill even the large inputs to the substation. > At some point you have to stop. No, you don't. The protections go all the way back to the power generation site.
  - pyrale 2y ago
    The transport/distribution network is hardly comparable to consumer appliances, though. The risks and costs are not the same. You don’t pay people to monitor your home electric network 24/7. You don’t risk damaging a power plant when there’s a short-circuit at home.
  - jcarreiro 2y ago
    This must be facetious? A GFCI breaker in a house's electrical panel and any breakers present in the transformer on the utility pole are protecting against _very_ different scenarios -- the breaker in the house is to stop someone from accidentally electrocuting themselves, but the breaker on the pole won't even notice an amount of current that could easily kill someone.
  - rtkwe 2y ago
    Nothing upstream of your electrical panel is sensitive enough to save you the way GFCI outlets are intended to. They aren't even sensitive enough to tell if your whole house is going up because of an electrical fire, they're there for downed power lines etc you getting zapped in the tub is barely a blip to those protection systems.
ralph84 2y ago
Yeah even putting aside the Temu specials, a belt and suspenders approach to not killing people does not deserve the derision this article gives it. The built in ground fault protection is there to protect the equipment not humans. In the real world stuff that “shouldn’t happen” eventually happens.
NewJazz 2y ago
They don't need a full exemption to GFCI, just the current raised from 5 mA to 30 mA.

by mike_d 2y ago

pkulak 2y ago

So then what’s protecting the protection? And that protection? At some point you have to stop. EVSEs have to be UL rated and conform to the J1772 spec. Their entire reason for existing is safety, and they basically don’t do anything else. They don’t modify the delivered power in any way. I guess they have a plug that’s rated for 1000s of connection cycles, but that’s really a safety thing too. Putting another GFCI behind that is a silly waste of time, money and another point of failure.

mike_d 2y ago
> So then what’s protecting the protection? Look out your window at the power pole, you'll see a transformer. That has breakers, differential relays, and other protections. > And that protection? Substations have RTUs and SCADA systems that are constantly monitoring everything for faults. They have cool shit like oil breakers that can kill even the large inputs to the substation. > At some point you have to stop. No, you don't. The protections go all the way back to the power generation site.
- pyrale 2y ago
  The transport/distribution network is hardly comparable to consumer appliances, though. The risks and costs are not the same. You don’t pay people to monitor your home electric network 24/7. You don’t risk damaging a power plant when there’s a short-circuit at home.
- jcarreiro 2y ago
  This must be facetious? A GFCI breaker in a house's electrical panel and any breakers present in the transformer on the utility pole are protecting against _very_ different scenarios -- the breaker in the house is to stop someone from accidentally electrocuting themselves, but the breaker on the pole won't even notice an amount of current that could easily kill someone.
- rtkwe 2y ago
  Nothing upstream of your electrical panel is sensitive enough to save you the way GFCI outlets are intended to. They aren't even sensitive enough to tell if your whole house is going up because of an electrical fire, they're there for downed power lines etc you getting zapped in the tub is barely a blip to those protection systems.

ralph84 2y ago

Yeah even putting aside the Temu specials, a belt and suspenders approach to not killing people does not deserve the derision this article gives it. The built in ground fault protection is there to protect the equipment not humans. In the real world stuff that “shouldn’t happen” eventually happens.

NewJazz 2y ago

They don't need a full exemption to GFCI, just the current raised from 5 mA to 30 mA.