Relay activates/toggles when NodeMCU is rebooted, or reconnected to the internet

[satyajitbagul]

Hi Nate, I recently added a NodeMCU and 5V relay to my garage door along with an open/close sensor. The setup worked very well. The only problem that I am facing right now is whenever NodeMCU reboots, reconnects or we make changes to the pins in Konnected(connect) app the device restarts and connect again to the WiFi and it also toggles/activates the replay. This causes the garage door to open (when it should stay closed). I was just wondering if there is fix that can be added the code which will recognize the last state of of actuator and not change it during reboot.

Hardware- Node MCU - ESP8266 Development Board NodeMCU Lua V3 WIFI with CH340G USB and Base Shield 5V replay - 2 Channel Relay Module With Optocoupler 5V Active Low Level Amplifier Trigger

Connections- VCC and GND of relay connected to NodeMCU 5v and GND IN2 pin of relay connected to NodeMCU PIN8 "+" of garage door connected to NO2 of replay "-" of garage door connected to COM2 of replay

Setting in APP- Low Level Trigger - Enabled Momentary Delay - 500 milliseconds

[heythisisnate]

You cannot use pin D8 with a low level relay, because D8 must be pulled LOW on boot which will cause the relay to trigger. The workaround is to use any other pin, or to use a high-level trigger relay on pin D8: https://konnected.io/collections/in-stock-now/products/1-channel-5v-relay-module-with-high-low-level-trigger

There's no software fix for this issue, as D8 is automatically pulled LOW on boot by the ESP.

[satyajitbagul]

Thanks for the quick response. I will try to change it according to your recommendation.

[satyajitbagul]

It is working perfectly now. I enabled high level trigger and swapped the "+" of garage opener to "NC2". Thanks for the help