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[Ethestral]

Coworker and I both have EV's mine has two wheels theirs is more expensive. I bought the diginow charging setup for my 16 DSR and its awesome. At home I wired a 50 amp, nema 1450 plug to use with my diginow J1772 adapter. I can piggyback both the factory chargers and the diginow to charge around 7.9 kw safely at home from the J1772 alone.

My question is about what is typically inside of a wall charging unit. If my coworker were to visit and use my "straight pipe" to charge do they risk damage to their vehicle?

Whats inside a wall charger aside from a nice relay or two connecting the voltage to a simple switch on the face? Are there conditioning circuits inside?

I would like to host but am afraid of cooking their car. I could take apart a free one at work but I have too much respect for EVI to just break something that's working.

[Burton]

They would likely require a EVSE to be able to use your "straight pipe" ...

Typically these are 14-50 to EVSE to Jplug style portable units which can be had for 250-500$

[MrDude_1]

An EVSE is nothing more than a safer wall plug that also says how much power you're allowed to use.

In short it decides if its safe to turn on. (aka, a vehicle is connected and requests it)
It then turns on, and watches the power.
If the power usage is too high, it turns off.
If a ground fault is found, it turns off.
If the plug is disconnected, it turns off.
If it is requested to turn off(via the vehicle) it does so.


How it works:
it boots up and checks ground, voltage, relay check, etc...
Circuit puts out a pilot signal and watches the voltage.
once connected to the car the voltage will change for it to know the state.. (connected, power requested, etc)
If connected, it should do a diode check.
It can then click on a big relay.
it checks that the relay is working.
it uses a current sensor to tell how much the vehicle is drawing.
it uses another current sensor to tell if there is a ground fault.


Its all pretty simple... just a stack of really simple, really cheap tech designed to be easy to implement and make the plug safer.
In the end, you are just plugging the vehicle into the wall and telling it how much the max it can use is. the vehicle then does its own thing.

[MrDude_1]

in your straight wires to a j-plug... most cars will not charge at all because they need the pilot signal telling them the max current they are allowed to pull.
if you add that, you have a no-relay EVSE.
if you add a relay, you have a bare-bones EVSE.

if you add the relay and safety checks.. you have a full EVSE.

[Ethestral]

Excellent information, thank you all.

At its most basic, no danger. It'll likely fail to charge as there's no communication at the wall for the car.

Lastly thank you for not jumping on the charging/char-ing spelling error I had in the title. The entire thread could have gone up in smoke.