Timed charging with SONOFF POW

[jarno83]

Hi, I have a question about type-1 charging with oem home charger.
Is it ok to use sonoff (POW 20A or 25A module) ) to switch charging on and off based of electricity price per hour in my region.
Does it do harm to car or charger if power is cut while charging? Anybody using it like that?

Thanks,
Jarno

 

[MickeyS70]

Hi, I have a question about type-1 charging with oem home charger.
Is it ok to use sonoff (POW 20A or 25A module) ) to switch charging on and off based of electricity price per hour in my region.
Does it do harm to car or charger if power is cut while charging? Anybody using it like that?

Thanks,
Jarno

While it’s never a good idea to remove a load under current, there doesn’t seem to be any (immediate) adverse effect as many owners can attest.

Usually this method is used to avail of cheap night tariffs and therefore the switching off under load happens only about once per 24h. I expect a higher frequency in your case, therefore best to interrupt the pilot signal rather than mains voltage similar to below

 

[kiev]

Does it do harm to car or charger if power is cut while charging?

Yes it will likely damage the On Board Charger.

 

[jarno83]

Ok, good to know. Then the plan would be to modify the oem charger cp line so it will go through sonoff or shelly or similar. Thanks

 

[VoironIon]

Hi Jarno,

Unfortunately do not use a switch to load charger while in use. You will damage on board charging circuit.

Fortunately, you can emulate switch behavior (the one located on the charging connector).

A relay can emulate the charging connector switch. It means that when charger is plugged to the car, while the switch is pressed nothing will happen. When relay disconnect it emulate a switch release allowing charging

If EV is charging it will safely shut off the load.

Open your charger, locate pin 4 and 5, and close it with a 1.3k ohm resistor in serie (best is to verify resistor value within the switch or charger PCB).


See here for plug pinout:

http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2015/54/html/M154955300005201ENG.HTM

See section 'Check on regular charging connector built-in switch'.


An illustration

 

[jarno83]

Hi Jarno,

Unfortunately do not use a switch to load charger while in use. You will damage on board charging circuit.

Fortunately, you can emulate switch behavior (the one located on the charging connector).

A relay can emulate the charging connector switch. It means that when charger is plugged to the car, while the switch is pressed nothing will happen. When relay disconnect it emulate a switch release allowing charging

If EV is charging it will safely shut off the load.

Open your charger, locate pin 4 and 5, and close it with a 1.3k ohm resistor in serie (best is to verify resistor value within the switch or charger PCB).


See here for plug pinout:

http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2015/54/html/M154955300005201ENG.HTM

See section 'Check on regular charging connector built-in switch'.


An illustration View attachment 678

Hi, thanks for your reply. Probably I end up doing a diy smart charger. There are some projects but haven’t found a perfect one yet.