Finder Override and Status Indicating Module, Power module 19 Series - Finder 19.91.9.012.4000, This Finder Override and Status indicating module is frrom the 19 Series. This relay is also known as intervention module. With the use of carefully installed intervention modules, a trained caretaker or security guard can be in a position to recognise any interruptions in service and by manual intervention perform the necessary override actions to maintain system operation until a repair can be effected. The 19.91.9.012.4000 is a 12V DC Power Module for Twilight Switch (order code 49-2931). Control via the semi-conductor output (Y1-Y2) of the twilight switch 11.91 (order code 49-2931). This output is controlled only by brightness and not by timer clock. With the twilight switch 11.91 and the power module 19.91 (order code 49-2932), it is possible to switch off some of the lamps during the night hours for saving power with 11.91 depending upon time and to maintain a reduced illumination throughout the night with the 19.91. Finder 19.91.9.012.4000 Power Module for Twilight Switch 12 VDC SPDT-CO