Ouch...... Not the best schematic/diagram to use as a go by.
First thing. This appears to be the kit from Sausagemaker you are talking about.
This kit provides the heating element and the blower along with their housings only. The rest of the control and power circuit is up to you. So back to that first thing. Map out all the components you want to use, and make sure they are compatible with each other before you buy anything.
The wiring of PID units is specific to brand & models within a brand. Do not use a diagram of someone's build as yours, as if you use brand X and he used brand Y components they may look the same, but no be electrically the same (may need to be wired totally different). Even within the same brand you will see different wiring diagrams for PID's for instance.
If you are building something to take the heat chamber up to 300* or more, you are not building a smoker, you are building an oven. I would not go with a wood frame structure with that heat target in mind. Got that info from your other thread. For those who may not have seen it, here is a link
http://www.smokingmeatforums.com/t/152386/electric-smokehouse-design-help
The reason I say this is you will also be heating the durock boards to 300* and they will also eventually conduct the heat to the frame of the smoker (which I take is wood from reading your smokehouse post). Screws would be the hottest and quickest point of conduction. I would be uncomfortable taking a wooden structure to more than 250* and would prefer to keep it in the 225* max range.
Have you searched this forum and looked at the other builds? There are quite a few threads with wiring discussions and some are 220v builds.
