WATERPROOF DS18B20 temperature sensor + Extra

Read temperature with reliability with the waterproof OneWire DS18B20 digital temperature sensor

Here is a pre-wired and waterproof DS18B20 temperature sensor. Convenient when measuring a temperature in a remote location or in a humid environment.

Although the sensor is able to withstand temperatures up to 125°C, we suggest staying below 100°C because of PVC cladding (the one used to make the sensor waterproof). 

As it is a digital sensor, we are immune to signal degradation... even over a long distance!
This digital sensor uses the 1-wire protocol (Arduino has a 1-wire library), is surprisingly accurate (±0.5°C over most of the measuring range) and provides information with 12 bit accuracy directly from the analog converter -> digital of BS18B20.

This sensor works perfectly with micro-controllers with a simple digital pin. You can even connect several sensors to the same digital pin, each of the sensors has a unique 64-bit identifier (engraved in the sensor at the factory) to differentiate them from each others. Usable with voltages 3.0 and 5.0V. 

The only gray area is that it uses the Dallas 1-wire protocol, which is quite complex and requires a lot of code to handle the communication. If you want a simple and trivial temperature sensor, we suggest the TMP36 which only requires an analog input.

This sensor is delivered with a 4.7k resistor. It is used as a pull-up to bring the data pin back to +VCC while using the sensor.

Technical details

Cable specifications:

• 6mm diameter stainless steel tube and 30mm length
• 91cm long cable, 4mm diameter
• Contain a DS18B20 temperature sensor
• If your sensor have 4 wires:
  Red connected to 3-5V, Blue/Black connected to ground and Yellow/White is the data pin.
  The welded copper wire is connected to the "shield".
• If your sensor have 3 wires:
  Red connected to 3-5V, Blue/Black connected to ground and Yellow/White is the data pin.

Technical specifications of the DS18B20:

• Usable temperature range: -55 to 125°C (-67°F to +257°F)
• Resolution: de 9 to 12 bits (selectable)
• Interface: 1-Wire - requires only one digital pin for communication.
• Unique identifier 64 bit (engraved in the sensor at the factory)
  Multiple sensors can share a single digital pin
• Accuracy of ±0.5°C from -10°C to +85°C
• Alarm system for "Temperature limit"
• Query executed in less than 750ms
• Can be used with a voltage of 3.0V to 5.5V (power/data)

Technical data sheet

• Download the DS18B20 technical data sheet.