OK, heres what I used to make my electric controller. I will tell you, this can be so simple. On Amazon I purchased a SCR 220 volt controller. You will see many of those, either with a twisting knob, or button pushing control. I got the button pushed controller, RioRand, 10,000 watt, 220 volt. That coupled to an electric element is really all you need to get it done.
I didn't stop there, I also got a box to install this in. I also got a switch, kinda like a breaker, 2 poles, 32 amp. I also got got a PID, very simple one, and the temp sensor RTD, 2.5" probe with 1/2" MPT. I went for the option to employ a male XLR connector and the braided 8' cable. There is another switch to turn the pump on and off... nothing fancy there. A light to let me know when the main switch is on... All from Auber instruments. The main wires into the box, and to the SCR and the female plug for the element are 10 gauge. The element came from brewers hardware, the one with a male plug end on it and to be put into a triclover. Very nifty setup, Spike also has the same thing going.
I'll get to drawing this up soon... really, it was simple... There is the electric brewery way, which I could've done, yet wanted an economical way to achieve the same thing, except I have to watch and control things... more cost effective and keeps you involved also. Sneezles61