Relay Issue

Having an issue with my relay module. When connected to an Arduino Pro Mini's onboard led the relay works perfectly. With the esp8266 on board led the relay doesn't trigger. It's almost like it doesn't fully go to ground. I've tried multiple pins as well as other esp8266 boards as well (wemos d1 mini and wemos d1 mini clones) but I can't find the issue. Any help would be much appreciated. For the sketch all I used was the blink example. Nothing fancy.

A LED is not a good digital signal source, it restricts the signal level to about 2V. If your relay module requires 5V signals, it may not fit together with the 3.3V ESP8266.

Why don't you program an output on each board to just switch the relay, rather than trying to use the current applied to the LED?
You will find it will be more predictable.

Tom... :slight_smile:

put NPN switch transistor on led output with 1k resistance to the base.Flyback diode on relay,emitter to ground ,collector to one leg of relay and on the another leg of relay plus(dependence of the voltage of relay).

So I'm using a songle srd-05vdc-sl-c
It triggers on 5v. Mistake found. I was kinda tired last night. I appreciate your help everyone.

What was the cause of the problem/solution?

Tom.. :slight_smile: