This additional control module, 18 mm wide, can be mounted on the standard impulse relay and features galvanically isolated contact levels. The devices are mechanically connected. It can operate between the local and central control stations with two different control voltage potentials (e.g., AC local, DC central). The central control module E294 is used professionally in various control voltage circuits. With this attachable additional device, a clean overarching and central command (all off / all on) can be realized. For such a solution, a central on/off control module must be installed for each impulse relay integrated into the central on/off control. Central commands always take precedence and reliably switch the mechanically connected coil of the standard impulse relay on or off, regardless of the previous switching position of the individual impulse relays.