Using the serial interface - SmartRelay 3 system

The digital outputs used for the serial interface are open drain connections. This means that a pull-up resistance in the data lines and 3–24 V_DC are required for operation as a serial interface. The O+ connection can be used for this purpose. A value of 1 kΩ is recommended. The earth system in the controller and the earth system in the third-party system must also be connected for data transmission.

You can obtain detailed information and the specifications from Support (see Help and contact). The required pull-up resistances may already be integrated in your third-party system. In doubt, please ask the manufacturer of your third-party system.

Wiegand 26-bit and 33-bit

The controller can communicate with systems which use one of the Wiegand protocols. Once an authorised identification medium is detected, the data are forwarded to the third-party system via the serial interface. The controller must be wired as follows to make this possible.

Primion, Siemens Cerpass, Kaba Benzing, Gantner Legic and Isgus

The controller can communicate with systems which use one of the protocols. Once an authorised identification medium is detected, the data are forwarded to the third-party system via the serial interface. The controller must be wired as follows to make this possible.