1-Wire is a very inexpensive bus system, which was developed and is mainly used for the acquisition of temperature values. Example: Pre-assembled 1-Wire sensor. Can be used flexibly, from the cavity wall box (behind the switch) to the outdoor area.


Easy setup via plug & play


Minimum power consumption less than 1mW

Flexible cable laying


  • Up to max. 32 sensors can be connected to one server.
  • Max. total cable length 150m
  • Different wiring topologies: star, line, tree structure


  • 5V supply voltage
  • Data line
  • GND


Optionally, 1-Wire can also be used in “parasitic mode”, i.e. in 2-wire operation. Then the sensor uses the data line as power supply. However, in this case a maximum of 20 sensors at 50 meters can be used.

When connecting the sensors, it is essential to pay attention to the color coding on the label. This may differ from the picture.

Line topology

Max. 10 sensors with max. 100m in total.

Star topology

Max. 32 sensors with 150m in total.

Tree topology

Max. 25 sensors with max. 100m in total.

Attention: Ring topology is not allowed!