Temperature monitoring with Dallas DS18B20 sensors and Domoticz
Jump to navigation
Jump to search
Sensors
We use the DS18B20 sensors, pre-mounted into a waterproof flange from the BrewPi project. These have RJ11 (6P4C) connectors pre-crimped, which we replace with the more common RJ45 (8P8C) connectors and extend the cable with a standard CAT5e FTP (or STP) cable. The connections are similar to the the common T568B color coding and the follow the 802.3af (Power Over Ethernet / POE) with respect to the DC +/- colors.
Sensor Pinouts
| Pins at switch | T568B color | 10/100 mode B, DC on spares |
RJ45 connector (8p8c) | RJ11 connector (6p4c) | DS18B20 flange-cable color | |
|---|---|---|---|---|---|---|
| Pin 1 |  White/orange stripe |
Rx + | not connected | empty (no contact) | ||
| Pin 2 |  Orange solid |
Rx − | not connected | not connected | ||
| Pin 3 |  White/green stripe |
Tx + | DATA | Vdd (+3.0V — +5.5V) |  Red | |
| Pin 4 |  Blue solid |
DC + | +3.3V | GND (-) |  Black | |
| Pin 5 |  White/blue stripe |
DC + | +3.3V | DQ (DATA) |  White | |
| Pin 6 |  Green solid |
Tx − | GND (- for data) | empty (no contact) | ||
| Pin 7 |  White/brown stripe |
DC − | DC - (for power) | |||
| Pin 8 |  Brown solid |
DC − | DC - (for power) | |||