Hello!

I need to monitor a 37kw pellet mill induction motor.

When motor power is above P_max, need to cut-off the power (the mill is blocked)

When motor power is under P_min, need also to cut-off power (sawdust is missing)

I want to use iammeter wem3080t to read the power and a sonoff/tasmota device that supply the coil of the motor contactor to be turn off and cut the power when the power is outside the (P_min - P_max) interval.

The sistem must not rely on internet, just LAN connection.

What do you recomand to use to implement this?

tnx

We have just posted a video tutorial about a similar usage.
Use the Modbus TCP sensor in Home assistant to request the data of the energy meter and control a sonoff relay (On/off) by the reading value from the Modbus tcp sensor.

The advantage of the Modbus/tcp sensor is it can request data more faster ,up to 1s/s.

https://imeter.club/topic/272

By the way,I remember the start of the motor should be do some "soft startup"(sorry for my limited knowledge about the control of the motor), if so,I do not whether the motor could be controlled by a relay directly. 

I think Home Assistant with a Shelly Uni  ( I run it on a Raspberry PI) to trigger a 24V AC or 24V DC contactor to turn the motor on would be perfect!

See https://shelly.cloud/products/shelly-uni-smart-home-automation-device/

I found this device pretty easy to set up in Home Assistant but I am only using it to  monitor water temperature in my hot water system .