I am building a powder coat curing oven that is about 6′ x 6′ x 8′ (I have some large pieces that need to be cured). I know typical home wiring quite well but electronics is another story. I need to heat this space to around 420 degrees f. I will only use the oven once a week at most so it’s okay if it takes a while to heat up. I am wondering how many heating elements I should use, what kind of SSRs to use (and do I need one for each heating element?). Then I would need a digital power controller along with a heat probe. Then there is the recirculating fan and anything else I may be over looking. Trying to wrap my mind around this project.
In the interest of liability, we must stress that what we are going to give you is merely suggestions, rather than instructions. Given that, ovens are a little bit out of our area of expertise, though I think that we can still try to help you somewhat.
Upon asking around for you, it was suggested to me that you should start by choosing an appropriate process controller, and then you should choose the SSR based on that. I was also informed that SSRs nearly always require some sort of heatsink in order to carry their maximum rated current, so that is another thing to keep in mind.
You will also need some sort of sensing device such as a thermocouple or TRD. Fortunately, modern temperature controllers tend to be very plug and play with just about any sort of TC/TRD input.