First time here posting as I have a problem that I can't explain and I'd like to get your help to fix it or at least understand what happened.
I have a 5v 4 channel relay connected to an ESP32 to trigger a command to control my awnings (open/stop/close).
Everything was working fine until today morning where the close action was not working. I've been trying to debug it since then and this is what I've found:
Channel 1 & 2 work properly with my ESP 32 being able to trigger them
Channel 3 (stop action) can't be triggered, I tried to manually trigger it with 3v and 5v. 3V does nothing, 5v the light of that channel turns on but not too bright. and I can ear a small noise
Channel 4 (never used) can't be triggered via ESP 32 or manually with 3v, but with 5v it's triggered
I've tested this with the ESP32 powering the relay as well as with an external power supply for the relay. Both produced the same results. It's really strange since no one touched the relay during the night.
Anything else I can do to try to understand what is happening and hopefully fix it or should I order a new one and consider this one dead?
Relays Dead - How long are they energized for? Also, can you swap your digital outputs, to verify that they work using your remaining two relays? There shouldn't be any reason for the ESP output to have failed, but it's worth checking.
Only for 1 week... I'd expect them to work for more time.
There's actually one thing that changed from yesterday to today. The relay and esp32 were hanging outside a ceiling lamp hole while I was testing it and I've moved them to the ceiling yesterday and put the light to cover the hole (the ceiling is dry and with mild temps, the esp 32 is there for more than 1 year and the lamp was not turned on). Don't see any problem here, but might worth mentioning it.
Yes I also tried the digital outputs on all the 4 relays to confirm that nr 3 and 4 do not work with any of the 3 I was using.
Even if it's a dead relay situation why did the nr 4 died without even being used?
Is the NO now closed so that the relay is conducting power all the time? If you use a relay with DC voltage on inductive loads such as motors it is common for the contacts to fuse together due to sparks from the collapse of the electric field. Do you have fly back diodes?
well, did it get tested when received, or was it just always dead?
Putting it in the ceiling cavity may mean it gets a lot warmer, depends on if the cavity has insulation or not, for one thing.
C
@pmagowan no they are still open , like I mentioned the relay nr 4 still works if I trigger it with a 5v.
The relays are wired to a RF remote and they just act like if it was me pressing the buttons.
@camsysca yes both 4 were tested and working. The ceiling is not much warm and it was during the night when is even cooler.
Can you post a link to technical information on all of the hardware items. Also posting a schematic, not a frizzy picture will be a big help. Show all connections including power and ground.
OP, the relay board you have requires 5V drive- because the LED and opto-isolator are in series. Those generic chinese relay boards are terrible for having missing specs and no schematic, mystery jumpers and scary spacings etc.
Note this critical spec (input voltage) is missing.
A MCU with 3.3V outputs is just at the low end and the relays end up starved of voltage. You'd have to short out the LED on a channel to get it working with 3.3V drive. I think temperature of the boards is the reason it sometimes works, and component variations.
