The19.91.9.012.4000 is a 12V DCPower Module for Twilight Switch. 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.
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