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1-Wire
1-Wire is a device communications bus system that provides low-speed data, signaling, and power over a single conductor.
UniPi tries to maximize the reliability of the whole network by serializing the bus as much as possible. This is achieved by using 4 wires (GND, VCC, Data-IN, Data-OUT). This four-wire design is used in our 1Wire temperature sensors and 8port hubs.
1-Wire thermometers
The DS18B20 is widely used 1-Wire sensor in TO-92 package.
- Power supply range is 3.0V to 5.5V
- Measures temperatures from -55°C to +125°C (-67°F to +257°F)
- ±0.5°C accuracy from -10°C to +85°C
- Converts 12-bit temperature to digital word in 750 ms (max.)
- Can be powered from data l
UniPi 1-wire temperature sensor
The Unipi 1-Wire temperature sensor is equipped with RJ45 connector, so it is easy to connect to the older variants of Unipi Neuron controllers or the UniPi 1-Wire hub. The newer variant of Unipi Neuron PLCs and the Unipi Axon product line both use a 3-wire screw terminal which does not support the RJ45 connector. To connect the 1-Wire temperature sensor to Axon or Neuron controllers, you can use two methods
- cut off the sensor's RJ45 connector, put ferrules on the conductors and screw them into a screw terminal connector included in the controller's package following this pin-out scheme
- use a cable reduction
The sensor introduces a 4 wire connection for better reliability of larger network, which can be converted to 3 wire version for simplification.