ESP8266 Community Forum

- Mon Jan 22, 2018 8:13 am #73376 I have a similar model but at 12 volts, even the relay is 12V, do I have to change the resistance values? Thank you.

- Mon Jan 22, 2018 8:14 am #73377

If you follow my directions, the ESP-01 will boot. Be sure to tie RST and CH_PD to VCC. Also, tie GPIO0 to VCC with a 10K resistor. If you actually want to be able to control the relay, then you will have to do the rest of the modifications in my post. (Removing the microcontroller, 4.7K SMT resistor, running a short jumper, etc.)

Once you get setup and going, it takes about 10 minutes modify each relay board. Then, I program the ESP-01 on an external programmer and install on the relay board. When the ESP boots, it will be responding to MQTT messages and you'll be able to change the software over the air (OTA)!

I have a similar model but at 12 volts, even the relay is 12V, do I have to change the resistance values? Thank you

- Wed Jan 24, 2018 8:27 am #73454 Hi
could you explain how you controlled this relay?
I do not understand it.

what firmware do you use?
what sketch?

thanks T

- Wed Jan 24, 2018 10:28 pm #73472

I have a similar model but at 12 volts, even the relay is 12V, do I have to change the resistance values? Thank you

The only 12V ESP-01 relay module I see on Aliexpress doesn't look anything like the 5V modules. The modification I outlined above won't work.

I would suggest to diagram out where GPIO0 and GPIO2 go. I suspect they are not tied to VCC or float, which will cause a booting problem.

Like the 5V versions, I'm going to "guess" the Tx and Rx lines go to a microcontroller that then drives a NPN transistor or an N-channel mosfet.

I'm afraid you will have to reverse engineer and diagram out the board.