Thanks I didn't know that.
But now I have another strange issue... I connect the Shelly EM to my heatpump because there is already a MID meter connected to it and wanted to compare how accurate it was. It was pretty accurate and only 2-3W off.
Today I picked up my Tesla Model 3 and I don't have a loadstation yet. For the time being I wanted to use a normal 16A socket with the mobile charger and use the Shelly EM to meassure the power into the car to I can make an expense note for the charging costs at home.
I was charging the car at 9A and I saw my housemeter go up to around 2400W. 370W was the powerdraw of the house so I was around 2100W for the car. But the Shelly EM reports 1150W. I tried it an hour later at 3000W and the Shelly was reporting around 1750W. It seems like the Shelly is only reporting about 60% of the real power draw. Does anyone has an idea why that could be? I moved the clamp around a little bit, but that made no difference.
EDIT: fixed the problem. The Shelly EM was connected to a different phase and seems to mess up the reading. I'm not sure if that was stated in the manual, but Googling helped me.