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DHT11 NC Pin
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DHT11 NC Pin

by felipedmsantos on Thu Jan 10, 2019 7:58 pm

Hi, I bought the DHT11 sensor and I'm curious about the fact that to have a NC Pin. What the utility this? I've searched in online foruns, but I only find speculations about factory calibrations, that is, nothing concrete... Someone can take off this curiosity definitifly?

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Re: DHT11 NC Pin

by franklin97355 on Thu Jan 10, 2019 8:32 pm

NC = Not Connected in this case. It can also mean Normally Closed in relation to a switch or relay.

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Re: DHT11 NC Pin

by felipedmsantos on Thu Jan 10, 2019 8:42 pm

Thanks for the reply, but the point of this question is: If I cant use this pin, why It exists?

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Re: DHT11 NC Pin

by franklin97355 on Thu Jan 10, 2019 10:50 pm

The product is made by a Chinese company so you would have to ask them. https://cdn-shop.adafruit.com/datasheets/DHT11-chinese.pdf

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Re: DHT11 NC Pin

by felipedmsantos on Fri Jan 11, 2019 3:46 pm

Okay, i'll do this, one more time thanks for the reply!

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Re: DHT11 NC Pin

by millercommamatt on Fri Jan 11, 2019 4:00 pm

My guess is that other sensors like the DHT12 are built with the same form factor and likely with the same PCB. All 4 pins are used on the DHT12. It's likely cheaper to make one board used for multiple products and just leave the unused pins in place.

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