A 4-port RJ45 breakout board to allow multiple one-wire DS18B20 temperature sensors on RJ45 and optical pulse sensor to be easily wired to a single RJ45 bus for easy connection to the emonPi or emonTx.

The emonPi / emonTx can support up to six temperature sensors and one Optical Pulse Sensor on a single bus. When using multiple temperature sensors and or an optical pulse sensor with the emonTx we recommend powering via 5V USB rather than AC-AC adapter due to increased power requirement. An AC-AC adapter can still be used to provide an AC voltage reference. 

An RJ45 coupler can be used to extend RJ45 sensor cables.

Documentation 

Optical Pulse Sensor Pinout