Hi folks!
I have gotten acquainted with the Shelly product line recently and immediately went out and bought some. I have had a Shelly 1 running for a couple of days now (needed that one for the dry contacts) and the next step was to install some Shelly 1L's in my light switches.
Yesterday I got the first one hooked up. Simple wiring with a single switch, controlling a light fixture with two 3W LED bulbs. It worked very well, firmware updated, configured, attached in Home Assistant, all was well. Until the bypass blew up. A fairly loud bang, and the main breaker tripped. That was a surprise. I triple checked the wiring diagram again and made 100% sure that I wired the things correctly. That conclusion also supported by the fact that the whole system worked fine for like an hour. I could toggle it remotely and physically, I could trigger my automations off of it, etc.
I figured I must've had a bad bypass, but fortunately I bought two. So this morning I installed the other. I came to the unfortunate realization that not only the bypass had blown, but the Shelly didn't switch the current on and off anymore. I could still hear the relay click, the web interface was working, etc, just no light. I assume there 's a fuse inside that's also blown.
Anyhow, I tried another 1L too. So a different Shelly and a different bypass to the first set that had blown. Again, it worked great. Didn't hook it up to HA yet, but I started trying different combinations of things. Turning it off from web, when the physical switch had turned it on, the opposite of that, etc. etc. All worked well and I was happy.
UNTIL...
I tried switching it on/off/on in quick succession via the web interface, and the exact same thing as the day before happened. A loud bang, breaker tripped and the bypass charred. Which makes me wonder, what's causing this? I see a couple of options:
- I wired it incorrectly. This seems extremely unlikely, since it's not a complicated schema, plus the whole setup worked fine, until I flicked the switch in the web interface a couple of times.
- I received not one, but two faulty units. This seems statistically unlikely, although I guess coming from the same batch, etc etc, it's not impossible.
- There's a design flaw in either the hardware or the software of the Shelly that's causing things to short. On the one hand that seems unlikely, because I guess the devices and software are pretty thoroughly battle tested by now, on the other hand, I can imagine not a lot of people have tried clicking the web button 5-10 times in very quick succession. Is that a legit use case? No. Should the product be able to handle that without stuff exploding in my home? Yes, absolutely. I'm not completely sure, but I think I was doing something similar when the first one exploded, because I wanted to verify how Home Assistant would handle the switch flipping while the previous automation hadn't finished yet.
So, I guess my questions are...
- Do these symptoms ring a bell for anyone?
- Is there another potential cause besides the three I've mentioned?
- Has anyone experienced this before?
- Is there a warning not to quickly switch the relay somewhere, that I missed?
- Is there anything relevant t
- hat I should know, but apparently don't?
Thanks in advance for your time!