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.