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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)
1-Wire temperature sensors
Unipi 1-Wire temperature sensors are based on a widely used DS18B20 1-Wire sensor encased in a TO-92 metal probe.
- Voltage range: 3.0V - 5.5V
- Temperature measuring range: -55°C / +125°C
- Accuracy: ±0.5°C (-10°C / +85°C range)
- The sensor converts 12-bit temperature values to a digital signal (750 ms max. delay)
- Can be powered by DATA wire (parasitic mode)
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:
- cut off the sensor's RJ45 connector, put ferrules onto the wires and wire them into the 3-wire terminal according to this schematic
- use the cable reduction and Unipi 1-Wire hubu
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:
- you need to connect a pair of sensors to Unipi Neuron or Unipi Axon controller using the 2-port splitter
- you need to connect a single sensor to an Unipi Neuron with the older RJ45 1-Wire port.
- you need to connect multiple sensors using the 8-port hub.