Node red is being used to control numerous different devices around the house and yard with some of those being fairly large components. Large meaning big current draws. Over the months and now several years I have gone through dozens of hardware designs to control those devices. The latest is a opto-isolator, transistor, fet setup which is working but bulky and costly, but again seems to be stable and long lasting. Originally used some 3.3 volt relays which ran for several weeks then failed. Either arcing closed, or failed to close.
Reading about all the different projects I am curious as to how others have managed in this area. Mainly how is the reliability of the different control circuits? While nothing I do is safety of life it's not fun having to redo circuits every several months and when some things fail it's down right annoying.
Thanks
I use Sonoff S20s around the house to control external lighting, so only small currents involved.
I did buy some of these solid state relays from Banggood (says they can handle 80A) a few months ago - but haven't used them yet. I did couple one of them up to a Wemos D1 Mini and can verify that they do switch with 3v3 logic. No doubt some of the other forum members will offer suggestions for you.
The specs look OK but I'd feel a lot better if you had said you had been using these for 10 years or so. The relays I started with had decent specs and a 10amp rating on the contacts. I was switching milliamps with them and within several weeks the contacts fused. These things were only switching maybe a dozen times a day which I think is fairly low usage. My skepticism is now significant about any parts that haven't been vetted by a user group or a good friend.
I have several Sonoff Basics, TH10s and TH16s switching heaters up to 8A 240V AC which have been running for a couple of years without problems. I have a rule never to load them at more than 50% of rated current.
Don't use relays for switching power DC, they don't like it as the arc on opening doesn't self extinguish the way it does with AC. Also watch out for inductive loads, even with AC, as that reduces the rating dramatically.
I flash them with the Tasmota s/w but other alternatives are available.
Small desktop fan can kill sonoff basic within weeks. Not meant for inductive loads. At least not for direct switching.
Read the manuals and don't do blind experiments. This is dangerous.
That is the worst of both worlds, DC and inductive.
For those that may not know what DC and inductive interaction is and why it can be ugly, suggest reading the following...
https://www.mouser.com/pdfdocs/EAO-TA-HMI-Inductive-loads-and-flyback-voltages-EN.pdf
All the DC based switching I have done is NOT with main loads, 5v and 12v, and well below 1amp current at most. So I can't say I have much experience with high loading, so I have dodged the issue thus far.
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