Platform: pi 3 model B+ OS: Rasbian Node-RED: 1.0.3 Node.js: v12.14.0 problem node: node-red-contrib-dht-sensor v1.0.4 node-dht-sensor: 0.4.0 bcm2385 libs 1.60 Hi everybody, I'm using a raspberry with node-red to control my heater - node-red-dht-sensor and node-red-heater. at the moment I ha…

one sensor? DHT22? I did. I've noticed the second one wasn't connected for a moment (several days) :rofl: and even with this mistake the first DHT did freeze

THe DHT series are slow and not very accurate. If you read them too fast, they will return rubbish. Best advice is not to use them at all - ever! It used to be that they were the only real option for a cheap temperature/humidity sensor but that is no longer true and there are far better options. B…

I've ordered 2 sensors DS18B20 to replace the DHT and test them. later, I4ll try again the BME280 because it has also some strange issues. but first, I need to have the temperature for my heater :smiley: next week I'll be able to test it.

[image] TotallyInformation: widely used DS18B20 With the proviso that they are indeed genuine.

[image] Bobo: With the proviso that they are indeed genuine. Definitely, only buy them from a reputable source, there are many dubious clones about. If they are very cheap then they may well be clones.

[image] Counterfeit DS18B20 Hardware I just found this in another forum: [edit] This link https://www.maximintegrated.com/en/support/faqs/ds18b20-faq.html also shows that the real DS18B20 is also a lot more accurate than we think!

to let you know, I've reboot yesterday evening the raspberry and it works... for how long :slight_smile: [WhatsApp Image 2020-01-11 at 11.35.26]

I also found the DHT22 to be very unreliable. They froze regularly on the Pi, less often on the ESP8266. Only power cycling the sensor would help. The communication seems to require very accurate timings. I dumped them all for BME280 (temp, humidity and pressure). Absolutely no issues with those, e…

[image] ghayne: the real DS18B20 is also a lot more accurate than we think! I can't see that in the link posted, but there is a lot there so I may just be missing it.

Here you go @Colin : [Screenshot_2020-01-11_11-00-52]

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DHT22 freeze for no reason

Hardware

ghayne 11 January 2020 09:39 10

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DHT22 freeze for no reason

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