It seems there are a couple ways to do this, but I haven't seen the exact solution I'm looking at so I wanted to check with the community on this. I have a 4KW patio heater I'd like to control with a countdown to avoid leaving it on for days.
An out of the box solution doesn't seem to exist, so I'm looking at controlling a 40A contactor with a countdown timer. I've seen solutions for a mechanical spring wound timer with a contactor, and a digital timer with a relay, but I'd like to use the digital timer with the contactor.
I figure it's easiest to just have everything at 240V, so I've speced a 240V contactor with coil volts at 240 as well, to avoid running a separate line just for the switch.
If the picture isn't quite clear L2 connects directly to A2 on the coil.
My understanding is that the mechanical spring wound timer, doesn't require a neutral.
The digital timer does require a neutral, so I can power it off of one leg coming in, and tie the neutral together. But this leaves 120V to the switch and 240V in the box, so I would need a common-trip 2pole breaker to power the circuit from the panel.
Anything else I'm missing here? Appreciate the help. This will be installed in a NEMA 4X box and I'll tie all the grounds to a grounding bar.
I'm getting conflicting solutions for low voltage solutions. What if I just used this timer? It's spring wound, which I don't love, but it's UL listed in the documentation from the supplier. And it's just one part for easy installation. Rated to 28A which should be sufficient for my 4000W heater.
If I were to wire it up with 120V. Would this be the right way to go? One side of the coil gets the white neutral wire, the other side gets a red switched hot wire from the switch. This seems to be the most straight forward in my head. Admittedly, and clearly, I don't have a ton of experience with 240V hence my confusion around neutral.