I have been searching the web to understand how to build (or source) a power regulator for to control the power to a 3 phase element in a brewing kettle. There are 2 elements that can be turned on/ off separately, but this still too much power with only one element running to control the boil to roll steady. The specification stated that the supply to the kettle is 31.8Kw/h 3 phase 55A, so if one of the elements is turned off the power control would be dealing with half these values.

 

Apologies I had not completed the thread.....
There is a SSD and PID which are used to control the switching of the power, but the lag of the sensitivity of the thermostat (PID) is not suitable as a way of controlling. I have read about controlling the PID manually with setting output %'s but the model I have (https://www.instrumart.com/assets/Autonics-TCN-manual.pdf) does not seem to this function. Any help to understand the best way to achieve this would be hugely appreciated.

 

I once did something similar but for a much smaller 3kw single phase water heater.
I ended up making a simple low frequency(1 or 2hz from memory) 555 pwm circuit to drive the SSR with a pot to manually adjust the duty cycle

 

I have been searching the web to understand how to build (or source) a power regulator for to control the power to a 3 phase element in a brewing kettle. There are 2 elements that can be turned on/ off separately, but this still too much power with only one element running to control the boil to roll steady

There is a SSD and PID which are used to control the switching of the power, but the lag of the sensitivity of the thermostat (PID) is not suitable as a way of controlling.

Thermostat and PID are not working, because intensity of boil depends not on temperature (temperature is stable), but depends on power level.
Control of boil intensity is possible, using water vapor, by such principle.