I put a power switch on my panel so I could include a safe start interlock. Got the idea from Kal. The nice thing is that I can plug the panel in, but to start the system I have to have the elements and pump all turned off. On top of that, because it's a momentary PB I have to physically be standing there, looking at the panel to turn it on. It's just another step to make sure that I don't dry fire the elements and that I'm actually ready to brew. I ended up with an extra momentary PB that I had other plans for but decided not to use, so I included that as a power off button. The off was probably completely unnecessary as I can just as easily use the estop, but I had it so I figured why not?