RS-485 Bus Wiring

The connection between the control unit and the control device is made via an RS-485 cable: recommended 4-wire cable, maximum distance 200 m, watch the terminal block polarity.

The connection between the control unit and the control device is made via an RS-485 cable. This specification is common to all LabKey readers that use this bus: Next, Mini, Glass and Extreme Vandal-Proof Keypad.

  • Recommended 4-wire cable (2x 0.22 A, B / 2x 0.50 +, -).
  • Maximum wiring distance: 200 m.
  • Attention! Do not reverse the terminal block polarities.
  • The control device is powered directly by the control unit.
  • Up to 8 control devices can be connected to the control unit (up to 4 for the 2-relay version), using a star or daisy-chain connection.

Example of RS-485 wiring

For mechanical wall mounting, see the page for the specific reader model.