I have 2 120VAC fans that I'd like to put on times and synchronize. I'm planning on using an ESP32, a few buttons, and a relay for the mains power. Each switch is a single-pole switch, so I only have to run one hot through a relay in each location.
What's the community opinion of this relay:
FOTEK SSR-40 DA 24V-380V 40A 250V Solid State Relay Module 3-32V DC to AC
Anyone have a better plan for synchronizing two AC mains fans with timer controls without running extra romex?
I used that exact relay in a project I did to control a water valve. It worked great, no heat. You will need two.
I have not used that brand but I have used a lot of them over the years without any problems. Be sure to put it in a proper enclosure.
Two comments:
Most units out there in the market are counterfeits, like the one you show in the picture. The main issue here is that instead of a 40A triac they may have triac with a much lower capacity, which can be dangerous in some cases. Make sure you get a genuine one. Try contacting your local distributor, not Amazon and the likes.
According to Fotek specs, you need 4V to turn them on, although I have succeeded with a counterfeit copy with a little less. This could be an issue, and you might require a (transistor) driver.
Otherwise, they are a good choice.
I was planning on putting it in the double-gang switch box in place of the switch that it's replacing, then tapping that same box for power for the rest in an enclosure on top of the switch plate. Is that a wise decision, or should I pigtail the main leads out too?
I'll buy from a reputable source then, instead of the listing in the original post.
I was planning on stepping down to 5VDC for the project. Using a mosfet to switch that for driving the large relay, then using a 5V tolerant esp32 board with its own regulator to step it the rest of the way down.
One source: Opto22 - Solid State Relays
I would still leave the existing mains disconnect or mains breaker so the relay and downstream parts can be worked on.
Breaker will remain in place and unchanged, just plan on replacing the switch in the box.
The fan is 120VAC, 720 watts, so I figure a 10 amp relay will leave me with capacity to spare.
