Hello Markus, thanks for your quick reply. 
My Shelly 1PM works with the firmware 1.5.6.
The status value is actually the displayed value without / 1000.
I found here “https://shelly-api-docs.shelly.cloud/#shelly1-1pm-status” that the status is not in watts hours but in watts minutes. Could that be the mistake? 
If that were so, you would not have to divide by 1000 but by 60000.
That would come closer to real values.
