Sorry if this is a stupid question, but I don't know how any of this works yet. I know that each shelf has its own heat tape and wires that connect to it, but I thought that all those wires have to eventually be connected to hook up to the thermostat. Doesn't the thermostat only have one connection? I have one already, but I haven't looked too closely at it yet since I don't have the rest of the things I need.