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Topic: DHT11 with external power (Read 447 times) previous topic - next topic

ttttkk

Hi, my DHT11 temp sensor works properly if my arduino is powered by a usb connected to a pc. But if it is powered by other external power the reading of DHT11 bounce.
How can I fix this problem? This problem doesn't occur on my other sensors like photocell.

MarkT

Sounds like either your alternate power is not stable, or you have shared the ground wire from Arduino to both
supply and sensor - keep sensor ground wiring separate from any ground wiring that takes significant current.
[ I won't respond to messages, use the forum please ]

robtillaart

External power should be at least 7Volts and max 12V
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

ttttkk

I tried using a DC 9V adapter and a 5V phone power bank. But both give me the unstable DHT11 readings.

robtillaart

Can you post a drawing how you connected everything?
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

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