Video: EVSE with grid monitoring vs 2000W water kettle. Will it prevent trip breakers?

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Piro

Well-known member
Joined
Feb 19, 2017
Messages
47
Location
Kraków, Poland
A test of Grid Monitoring used in Accelev https://www.facebook.com/EVSEChargerAccelev/

Car loads with a max speed of 16A, as the breaker is 16A. Then I start a water kettle (2000W) - once with Grid Monitoring at charger is on the second time - off. I restart charging, as charger needs 1 minute to go back to full speed after switching off the kettle.
The charger detects load (water kettle) and immediately slows down charging. Without that function (with cheap Chinese chargers like Duosida or Zencar) - breakers will be switched off because of grid overload.

https://www.youtube.com/watch?v=FNOAODC7wnk
 
Just curious how the EVSE knows the current draw of the kettle, so it knows how low to dial down the EVSE?
Does it simply monitor the voltage and when it detects a voltage drop it lowers the draw? Not sure how well that would work.....
The only other way I'd know of would be to have a current sensing device tied to the breaker or kettle outlet and dial down the EVSE that way, of course that would be quite a bit more complicated to implement.
 
What I do not understand with these dynamic current EVSEs is HOW they communicate their real-time maximum current over to the car. Since the charger is actually in the car, it seems like there is a constant data link between the car and the EVSE, and the EVSE is periodically reporting the max. current available. Is this how it works? Any heads-up to the theory on how this works?
 
thanar said:
What I do not understand with these dynamic current EVSEs is HOW they communicate their real-time maximum current over to the car. Since the charger is actually in the car, it seems like there is a constant data link between the car and the EVSE, and the EVSE is periodically reporting the max. current available. Is this how it works? Any heads-up to the theory on how this works?


Does this have to be how it works? The onboard charger in an EV will use whatever current it is given, from a certain minimum, to its maximum. I don't see why it has to know how much current it is getting from moment to moment, since it is designed to use any current value in that range...
 
thanar said:
What I do not understand with these dynamic current EVSEs is HOW they communicate their real-time maximum current over to the car. Since the charger is actually in the car, it seems like there is a constant data link between the car and the EVSE, and the EVSE is periodically reporting the max. current available. Is this how it works? Any heads-up to the theory on how this works?

There is a pulse width modulated signal communicating the maximum current the EVSE can supply. Continously.

https://en.wikipedia.org/wiki/SAE_J1772#Control_Pilot

Current sharing EVSEs, with multiple cars connected, will dynamically adjust the currents allowed to each car. This is quite similar.
 
Back
Top