The call station module is used to make custom-made call stations, with the same functionality as the LBB 4430/00 Call Station Basic. The module is powered from the Praesideo network, but an external power supply can also be connected. Two supervised control inputs can accept power supply status information from the external power supply. The PRS-CSM can be extended with up to 16 keypads (LBB 4432/00 or PRS-CSKPM), each with eight programmable keys. Extension with a numeric keypad (PRS-CSNKP) is also possible.