Hey all. Ive been pulling my hair out over this for some time now. I used a nodemcu to run konnected and that worked well, but I migrated over to EspHome. To be clear, its not a configuration issue. Rather an installation issue.
One of the zones keeps damaging the pin it is connected to. I have gone through 3 separate nodemcu’s because of this. At this point, I dont want to destroy another one carelessly, so Im hoping some of you can assist me.
I know about EOL resistors but from what I understand, those are only useful for detecting faults for powered sensors, not contact sensors. Correct me if Im wrong though.
I measured the resistance on the specific zone and it reads at 0029 ohms. This specific zone, as well as another one is a series of windows and 2 doors. The other one is just windows. Considering the series of sensors, Im including it just to cover all the bases.
Am I missing a diode, or specific resistor to connect? Is there anything specific I need to get to address this because Im missing out on valuable information due to this.
Should also mention that sometimes the zone 5 entity switches between states quickly, indicating a floating pin. Sometimes it does this, other times it doesnt. Each pin is configured pullup, so the configuration is not the issue. I think at least.
What all am I doing wrong and need to change? Thank you all!
I checked the zone and they are those cap style contact sensors. At the alarm box, there is a wire coming from the wall, and its internal wires are sheathed green and red.
The zone in question (5) is wired red to an ESP8266 breakout board and screwed in to pin D6, with the green wire screwed into ground. The ground is shared by another 2 zones (ground wires are split between two screw terminals).
When all windows and the two doors are closed, the circuit is closed. When one of those windows or doors is opened, the circuit is opened.
It is pulled up. Each configured pin is configured pulled up. The damage seems to only occur on zone 5. It occurred once on zone 6, which is just windows.
If it helps, they also have to be set inverted.
Can you rule out, for example, one of those zone wires passing close to a mains cable and geting some sort of inductive “kick” when you turn (say) a light on?
I actually haven’t tested that. Since I am alone, it will take some time. However, I can mention that when the pin floats, it switches like a bat out of hell. Is it possible that a sudden inductive load blows out the internal resistor? Or a loose connection can cause the resistance to go crazy? One nodemcu has the damaged pin floating, and the other one has a completely dead pin.
Tested the zone and noticed that AC voltage blipped several times between 0 and 0.2.
One of the doors tied to this zone is located a few feet away from the breaker panel, and the electric meter.
Although it would take a long time to determine what and when something occurs to damage the pin, I will most likely try an octocoupler and see if it helps. Given that three nodemcu’s have been damaged, there is either something wrong with the wiring in the house, or there is something wrong with the way Ive connected the esp unit. Instinctively, I went with the latter.
Sorry
I ve changed 3 nodemcu because of pin not working ( can’t remember if was always the same ) after 1 month of normal usage. This happens in two different board. One sensor for each Konnected board always shows open state after a while. Did you solve with the octocupler?
I actually havent used an octocoupler if Im honest. So far, the board I installed seems to be working well. I decided to split the ground connection wires to two ground pins, to even the distribution. I also chose to use a breakout board, like this.
The important thing is to make sure the connections are strong and solid. It looks like even a slight loose connection anywhere in the line was causing problems for the esp board.