Openevse always starts on 24A and keeps cycling "openevse module is missing"

Hi, only just got the openevse unit up and running but it’s not really behaving well. I can change the charge rate (current) but it makes no difference. The unit seems to reset in a cycle where charge starts at 24A all on its own without me setting it, then webpage says “websocket disconnected” and I am unable to stop it, then it stops itself and says “openevse module is missing” and the charge stops. A few seconds later it restarts charging at 24A even though the “Charge Session” toggle is set to “disable charge” and the Charge Rate is anyway set to 6A.
Looking at the lcd screen while this is happening I can see it going through its start-up cycle displaying web address etc.
It doesn’t disconnect websocket and restart when the system is not charging or perhaps without a vehicle connected so could the current flowing when charging be upsetting the openevse module or the wifi module ? It’s a 5.5 with firmware 8.2.2 and wifi module is esp32 with firmware 5.1.0_modified.

Any help would be much appreciated.

Problem seems to be solved. I detached the wifi board from the aluminium backplate that it was mounted on. I suppose there was some interplay between the controller, which is also attached to this aluminium backplate and the wifi board or just that the ally plate picked up emi from the much bigger mains current when charging started, causing the shutdown/restart cycling. Anyway, it seems to have stopped the shenanigans !

Hi,

Just to be sure I would check the earth connection to the EVSE. This is connected to that backplate and will also be providing the protective earth to the car.

John

What, do you think the earth is perhaps bad ? It looks good to the eye but I have not tested it and sometimes the car will say “charge impossible” which I believe can be because the car (a Zoe) measures too high earth loop impedance or earth to neutral impedance.

Spoke too soon, tried to charge the car just now and had the same sort of behaviour: “websocket disconnected”, charging starts at 24A (even though set to a different charge rate), then disconnects, resets etc.

I will check the wifi board has not come back into contact with the backplate and I am going to order an ethernet gateway in case it’s a wifi problem. Mind you I would be disappointed if the module was “supposed” to behave like that on loss of wifi.

Hi,

not 100% sure how to test the quality of the earth on other systems as I live out in the sticks we have an earth rod not the looped neutral that more modern systems have (though I have seen that an earth rod is recommended by some if you have an EV) I would first check that the wires and connectors all look good and tight/secure If you have a multimeter you could check the AC voltage between your earth wire and something metallic pressed into the ground (if the ground is dry ensure you soak it first) it should only be a few volts max.

John

We have an earth rod also, a TT system I believe.

I have had a few problems with nuisance tripping so I installed a 100mA RCD on the incoming supply which then feeds a number of 30mA RCDs. Some of the nuisance tripping was caused by the car which has a certain amount of earth leakage. This nuisance tripping would lead me to believe the circuit that supplies the car charging has a good enough earth or the tripping because of leakage currents totalling 40 or 50 mA probably wouldn’t happen.
Any thoughts on the “websocket discconects”, random restarts, charging at 24A even though set to another number ?

Hi,

the web disconnects are when the module is rebooting or the wifi module is rebooting. Not a clue why you get a 24A max other than that if the car or a demand shaper is lowering it.

John

Apparently this behaviour of rebooting on loss of wifi is “normal”. I’ve asked if there is a firmware version that doesn’t do this but unfortunately not.
After the reboot it automatically starts charging on max which in my case is 24A. The 24A max is just what my model of Openevse allows, I don’t know why.