1-Wire bus

1-Wire is a communication bus system designed for low-speed data transmission, signalling and power through a single wire.

Unipi 1-Wire products are designed for reliability and serialization. For this purpose, Unipi 1-Wire sensors and hubs use a four-wire setup (GND, VCC, DATA-IN, DATA-OUT)

Unipi 1-Wire temperature sensors are based on a widely used DS18B20 1-Wire sensor encased in a TO-92 metal probe. The sensor converts 12-bit temperature values to a digital signal (750 ms max. delay)

  • Voltage range: 3.0V - 5.5V
  • Temperature measuring range: -55°C / +125°C
  • Accuracy: ±0.5°C (-10°C / +85°C range)
  • Can be powered by DATA 1 wire

Unipi 1-wire temperature sensor

Unipi 1-Wire temperature sensor is available in four cable lengths, and features an RJ45 connector. It can be connected to older Unipi Neuron controllers with RJ45 1-Wire port, or the Unipi 8-port 1-Wire hub. The latest Unipi Neuron design and the entire Unipi Axon line are equipped with 3-wire screw terminals, for which the RJ45 connector cannot be used.

If you need to connect the sensor to a controller with the 3-wire terminal, there are two methods you can do so:

  1. cut off the sensor's RJ45 connector, put ferrules onto the wires and wire them into the 3-wire terminal according to this schematic

Possible connections

Connecting a single 1-Wire temp. sensors to a Unipi controller

Connecting a pair of 1-Wire temp. sensors to an Unipi controller using the RJ45 splitter

Connecting multiple sensors using the 1-Wire hub

Creating a network of 1-Wire sensors using multiple 1-Wire hubs

1W-T-IB2 / 1W-TH-IB2 on-wall temperature and/or humidity sensors

Unipi product listing also contains the 1W-T/H-IB2 compact on-wall sensors for measuring temperature (1W-T-IB2) or temperature and relative air humidity (1W-TH-IB2) in building interiors. The sensors feature a four-wire screw terminal and can be modified for connection both to 3-wire connector and the RJ45 connector.

Connection options

3-wire screw terminal

This option is suited for cases where you need to connect only a single sensor to Unipi Axon or Unipi Neuron controller

RJ45 connector

Modification for the RJ45 connector is useful in three major cases:

  1. you need to connect a pair of sensors to Unipi Neuron or Unipi Axon controller using the 2-port splitter
  2. you need to connect a single sensor to an Unipi Neuron with the older RJ45 1-Wire port.
  3. you need to connect multiple sensors using the 8-port hub.