The GSM alarm module (GSM = Global System for Mobile Communications) enables cost-effective remote control of industrial and private building management, e.g. of heating, air-conditioning and cooling systems. In the event of a fault, fault signaling units enable fast fault localization of all monitoring devices and limit monitors installed in a plant from a central location and thus increase plant availability. EMERGENCY-STOP circuits are common safety measures in laboratory equipment and industrial plants. Dusk switches are used for the demand-oriented switching of lighting installations for shop windows or paths in order to cut operating costs. Additional functions include the level monitoring and temperature control, as well as the monitoring of asynchronous motors for underload and no-load operation.