4 HN users recommended this explainer4 months2021–2024score 4.5
Years with an HN recommendation, 2007–2026
HN recommends it as the clearest introduction to what is inside an AC EV charging station and why it is much simpler than people assume.
Technology Connections explains that the so-called EV charger in an electric car's charging cable or wall unit is really an EVSE, a smart switch that safely delivers AC power. The actual charger is inside the car. The video covers the safety signaling and mechanisms involved.
“A quick intro into EVSE and why there is no power 'charger' in them” (HN, 2021)
In case you don't watch Technology Connections... 1. You probably should, Alec is great. 2. Here's a longer broader video about what goes on in an EVSE: [this video] There are too many comments to go sling context left and right, but generally an EVSE is a controller board (what this is implementing), a contactor (this board uses relays), and a GFCI (in North American parlance), which his RCBO provides along with being a current limiting circuit breaker. Contactors are generally better for these use cases for reliability and current handling reasons but it wouldn't surprise me if SCRs and Relays are in use in low cost 16A EVSEs on Amazon.
Broader explanation of what goes on inside an EVSE
I'm not an electrical engineer, but from watching this video [0], there seem to be about a million and a half different mechanisms to prevent sparks from chargers. [0] [this video]
Shows the many safety mechanisms preventing sparks in EVSE
A helpful video about what's inside an AC EV "charger": [this video] Really the only difference with the fancier ones is they have a screen and payment terminal or NFC terminal for activating and paying. Like a gas pump, although most want you to use their app and membership to save (them) on credit card processing fees. DC fast chargers are a whole different story, where the AC to DC conversion happens external to the car.
I'm curious how many EV purchasers live in single family homes, or other places where they can provide their own ability to charge at home. I wonder if a new scale of adoption will require a change where most (or a lot) of street parking is by cheap charging. [this video]
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