The GD 475-S has the same functions as GD 475 with transistor output and must be connected to the control panel via an IU 400 interface/analyser unit. The detector has a coiled cable with a modular contact which is connected to the junction box JB 103-4, which allows it to be quickly and easy disconnected from the detector loop when, for example, cleaning windows. The signals from the detector comes on pin 5 and 6 in JB 103-4. Which is connected polarity independent to IU 400-Pin 3 and 4.