We have a Shelly 1PM controlling when our Sunamp charges, normally overnight.
On two separate occasions now it's turned itself off due to "overpower consumption detected" (as reported on the Shelly app and by email). I've check the resistance of the Sunamp immersion and it's 18 Ohms. I think that's 'normal'.
I checked the mains voltage in the wee small hours when it tripped out, and in the couple of minutes that I was monitoring it the voltage varied between 249.9 - 250.9V (it's now hovering around 248V).
The Shelly 1PM trips out at 3500W. If my Googling is correct, when the voltage hits 251V the Watts will exceed 3500 tripping off the Shelly. Does that sound about right?
I realise the DNO can pour 216.2 - 253V into the house and as we are right by the sub station we get the upper end of that range.
So, to the main question, is there a small voltage regulator out there that can control the voltage to the Sunamp or will I have to get rid of the Shelly?
Are there any other solutions?