How many sensors can the nodemcu handle?

I have a NodeMcu board and I want to connect 8 sensors dht22 and to trigger one relay through his.

My worry is overcharge in my board, this is possible?

I want to use the Blynk for it.

Looks like you have enough gpio pins on there so 8 sensors and a relay would be doable I guess?

"Since several lines are used internally within the ESP8266 SoC, we have about 11 GPIO pins remaining for GPIO purpose."


This is nonsense! I’m not even sure what you are trying to say? Are you asking if powering your sensors from this board will pull to much current, then the answer is possibly. You should not power ANYTHING from your controller, the pins are data pins, NOT power pins.

I want to say… Each sensor needs to be connected to 3v3 or 5 v, thats right?! If I put 8 sensor in same time I’ll overcharger my board?

What power supply are you using to power "your board"?

From the datasheet here

7. Electrical Characteristics:
Item Condition Min Typical Max Unit
Power supply DC 3.3 5 6 V
Current supply Measuring 1 1.5 mA
Stand-by 40 Null 50 uA
Second 2 Second
 *Collecting period should be : >2 second.

1.5mA *8 sensors =12mAh. Guess that won't be a problem :open_mouth:


Autocorrect on phones. They produce some good memes too xD

you could use an I2C relay board/boards

With the DHT sensors you're limited to physical pins on your board, you can not read them over a port extender.

Other than that... no real limit. I'm quite close to finishing a project that has 8 proximity sensors, 8 water flow sensors, a pH sensor, EC sensor, temperature sensor, water level sensor, and some 13 12V switched outputs.