DS18B20 single Sensor how to connect - main site link dead

I have an emonpi and I want add a single sensor to it which I understand I can connect directly to the emonpi with a RJ45 connector.

Some time ago I saw a link which is meant to show how to do it but the link seems to be dead, the link is on this page emonPi / emonTx RJ45 to Terminal Block Breakout for DS18B20 - Shop | OpenEnergyMonitor its highlighted as ’ DS18B20 wired directly onto RJ45’ but that link is dead.

Can anyone tell me how to do this I have a sensor and I know how to wire RJ45s, but I don’t know what pins are needed to connect it.


The dead link goes back to an old Shop page (@Gwil please note - link to the emonTx Wiki page instead? Also the emonPi Wiki has the same bad link here: EmonPi - OpenEnergyMonitor Wiki).

The information you need is in the emonTx Wiki EmonTx V3.4 - OpenEnergyMonitor Wiki

Hi Robert thanks for that link however I am finding it a bit confusing, the picture of the RJ45 shows a cable with 4 wires(green/red/blue/brown) which are different to the 3 that I have on my sensor, mine have 3 wires (red/black/yellow).

I assume that red is +ve and black is -ve and yellow is data so am i right in thinking that I should wire the RJ45 with data on pin 4 and +ve on pin 2 and -ve on pin 1 or 3?

The 4-wire cable is obviously a telephone-specific type with those colours.

I am fairly certain your assumption will be correct. Any GND will be fine, they are all commoned on the PCB.