I would appreciate the “bullet-proof” solution too! Cheaper and more reliable…
Not sure if a 3 phase contactor + 1 Shelly is indeed cheaper than a S3Pro these days! All my local electrical shops are selling ABB, Hager, Schneider, Legrand etc. etc. brand DIN 3-phase contactors for anywhere from EUR 60~120 depending on spec. But I'll probably go this route all the same. Pulling up a broken borehole pump from 200m+ is a huge pain and definitely more expensive than a contactor 
I bought a couple Shelly 3 Pro for automating various 3-phase pumps. During my bench tests w/ Home Assistant I notice that the three relays aren't triggering 100% simultaneously (there is a very tiny delay as the relays engage; always in the same order 1-2-3, with approx. 0.25 seconds gap in between each relay).
I'm not sure if this is due to Home Assistant / network delays etc. causing sequential triggering... But my question:
Is there any way to gang all the three relays together within the S3Pro firmware, and trigger all relays as *one* single device / entity (instead of three individual devices / entities)?
Note: My concern is to avoid the (very small) risk of one-of-three relays not 'getting the message' from Home Assistant and my borehole pumps being forced to run on less than 3 complete phases. Many thanks!
Note 2: Yeah, my alternative option is to use a single-relay type Shelly plus a 3-phase contactor (which is probably the more bullet-proof solution).
OK great thanks!
I have a feeling that I may have slowly killed this Shelly, it should have been OK according to specs (the heater draws max 2600W @ 240V), which is below the 16A limit.
In the end I used a Shelly to remote control a 25A DIN contactor in the main circuit box for the water heater. I lose the power metering capability, but the Shelly can't overheat.
Hi all, title says it all. I'm using a Plus1PM to control a ~2500W water heater, and it's been fine for the last 5-6 weeks. However the Plus1PM switched off the boiler twice today (the relay to the heater switched off; the Plus1PM kept running OK).
I'm curious how hot the Plus1PM needs to be before switching off the relay due an Overheating incident?
Many thanks!
Dan
After some digging around I think I can get what I want from an ESP8266 board running ESPEasy. But ideally if Shelly have a product I prefer to use that! DIY is fun but horrendously time consuming
Title says it all really.
I have an old sliding gate which I've retrofitted with a Shelly 1Plus (a wifi relay w/ a 1 second timer, that mimics a user cycling between open > stop > close etc.) and Home Assistant.
What I want is to do is get notifications in Home Assistant when the gate is open or closed. Is the Shelly Uni the correct product for this? Or something else?
Note: Inside the existing gate control unit there are 2 microswitches – one is 'on' at open-stop and the other is 'on' at closed-stop. When either microswitch is 'on' I measure 24VDC across the microswitch terminals. I thought about hijacking this 24VDC power to run a Shelly device, but when each microswitch is 'off' then 24VDC no longer exists across the terminals: As if the gate control unit 'flip-flips' power to the microswitches. I don't fully understand the logic to be honest.
My gate control has 24V*AC* auxiliary power terminals, but no DC aux power. And I could use the 220VAC mains power.
Anyway, assuming I can find power somewhere, what Shelly device can I use to get the open & closed status of the microswitches? Thanks in advance ladies & gents!
OK – got it working – for people searching the forum in future. I'll draw up a schematic later this evening.
Basically don't install the Shelly Plus 1PM at the (2-wire) switch and try to find the junction box that services both the switch & lights.
Cheer, D
Update ... possibly figured it out ... install the Shelly here, instead of at the switch. The two wires from the switch connect to L and SW on the Shelly, then figure out the rest 
Bit confused with this light switch, I was expecting more wires, but instead I've only got two
Black L, brown N, so I can get the Shelly to power up OK.
I can also get the Shelly to recognise the switch input, as wired in the attached photo.
I'm having a mental struggle trying to figure out how to close the loop with the relay (so that the lights work).
Thanks, D
