AZDelivery 5 x DS18B20 Digital Temperature Sensor TO92-55°C - +125°C compatible with Arduino and Raspberry Pi, including E-Book!

Perfect replacement for CCTV camera temp sensor.

AZDelivery 25 x DS18B20, Digital Temperature Sensor pack is a practical choice for projects needing multiple temperature measurements. While they offer good value and ease of use, be mindful of potential accuracy variations and verify the authenticity of the sensors for critical applications.UK- all tested and worked well at a good price.

These work and are very precise. With 5 devices that can all be accessed on one bus, it is apparent that the accuracy varies between devices. Precision and accuracy are of course different so that all devices are within spec.All this means is that the devices are able to precisely identify a temperature e.g. 38.0625C from 38.0000C but between devices, there is a variation e.g. calibration that the spec allows for +/- 2C differences. Using one sensor by itself is OK, but to use a second sensor requires it to first be calibrated to the first device.A program in an Arduino can be adjusted to allow for the variation. The device has EEPROM storage that can be used to record and correct any offset. Once calibrated and the program knows the offset, they become "plug and play"Since all the devices are technically within their specification and the price is very low, you can't complain too much. Almost all devices have wide tolerances and this is no different. With five devices they can easily be calibrated with each other e.g. using a block of ice or similar.When measuring the temperature there is the option to use 9 or 12 bit operation. The advantage of 12 bit measurement is the precision of recording temperature variation as each bit doubles the resolution. It also increase the time to make a measurement and 12 bit takes about 750ms. Whilst you might wait for a reading to complete, it is better to configure the device to be non-blocking. This just means you can read the temperature and immediately request it again. After doing something else, the temperature reading will be valid after 750ms. So it is worth exploring the options of a driver e.g. for an Arduino.AZDelivery provide a manual showing operation and programming that is free to download. Just go to their website and "order" the booklet (no CC and it's free). At the very least it shows the operation and code with an Arduino or Raspberry Pi and has some tips for using it. For a very detailed measurement, few other devices come close to this.

I've only used 3 of my set of 10 so far, but each one has been precisely what I needed. Easy to mount, good documentation online and delivering readings within tenths of a degree of each other; more accurate than I really need.I've used them on my Raspberry Pi for a quick prototype and was up and running in minutes, super easy.I've also hooked one up onto a bespoke ARM board I work with and the setup and results were equally as simple and accurate.

With three wires - two for power, one for data - and a pull up resistor, I've connected these to various Raspberry Pis and Arduinos around my house, feeding back to databases that allow me to graph temperature change. I'm only using one per device, but they can be connected together without needing extra pins. Inexpensive and useful.

*EDIT*: All 10 received do in fact work and all consistently report somewhere around 10C high. My original tests used a board that already had a 10k pull-up I was unaware of, which was too strong in parallel with the 4.7K.*ORIGINAL*:Obviously these aren't originals, however in the pack of 10 only 3 were any way usable. Those three reporting the roughly correct ~18-22C ambient temp. The other 7 varied from -8C to 100C to just all kinds of random values.You may get some that work but overall they're very untrustworthy.

Really easy to use with Raspberry Pi following the available tutorials.Datasheet provided by seller as well.

Most of these devices are not to specifications. They are clones of various types of the original.Some do not support all the features like the unpowered option.But they are good value if they do what you need.