OT: Electric Car Charger

[Roger Mills]

I've already got 25mm^2 tails between fuse head and meter - which I think were upgraded when the meter was changed some years ago.

[Roger Mills]

What DC-DC converter? Home charge-points - even the 3-phase 21kE variety

- feed AC to the car. AC to DC conversion is done in the car's inbuilt charger. [Some cars can also accept a DC input, but this is only available in ultra-fast chargers at motorway service stations, etc.]

[Roger Mills]

Nothing wrong with that as long as it gives you sufficient time to charge up for the number of miles you need to do. If you were doing hundreds of miles per day, this wouldn't work.

[Fredxx]

My wrong, I though the charging points were smarter than that. I guess it's obvious that the charging would be an in-car module.

That also then gives rise to the question if the in-car charger is double insulated, less need for a local earth.

Most wiring I have have seen for external chargers has been SWA, which doesn't need any RCD at the feeder end. So just one needed in the charge-point.

[charles]

My 32A charge point gives me 24 miles of motoring in an hour. I'd assume that a 13A would giive about 10 miles.

[newshound]

Current transformer, Arduino, keypad to accept a code that you give out, contactor to power it up when it gets a good code. Log data to SD card or better still wifi it back to your LAN.

This is DIY, after all.

[williamwright]

You can't miniaturise the Watt.

Bill

[Tim+]

Pretty sure there?s such a thing as a milliwatt. ;-)

Tim

[Andy Burns]

in where? What most people call a car charger is not much more than a mains relay, DC chargers aren't really for homes.

I found a 32A 230V transformer (for isolating the shore supply to a boat) it cost nearly a grand and weighed 24kg ... I think I'd stick with a type A RCD.

[Chris Green]

I'm not sure if you realise but the whole point of a *transformer* for a boat supply is to provide galvanic isolation for the boat to prevent (or at least reduce to a negligable level) corrosion of a metal boat. To do this it has to be a real, double wound magnetic core transformer.

A "type A RCD' would be rather irrelevant to such a connection.

[Andy Burns]

Yes I'm aware, but I was just using it to illustrate that a transformer to handle that much power is no small device that you could just build into an EV "charger"

but it would be relevant for a car charger, which is what is being discussed.

[The Natural Philosopher]

It doesn't ...

it can be if you use high frequencies. E.g at 50kHz it can be 1000 times smaller...

[Chris Green]

OK, I'll disappear back down my hole! :-)

[Tim Lamb]

The last time I played with anything that clever was when the BBC B was in schools!

Probably 75m or so to the furthest and not particularly line of sight.

Still if it is that easy, there ought to be an affordable unit somewhere.