Safety device for warning of excessive amount of water collected on flat roofs, comprises casing and float with cooperating contacts

摘要

A float (1) provided with a contact (7) is mounted inside a casing (2) for mounting on the roof (3). The casing has a lower contact (9) for indicating little or no water is present and an upper contact (7) for indicating that the water level (6) has reached a dangerous level. As the water level rises, the float rises and in the event of the water level becoming dangerous, the contact on the float forms a circuit with the upper contact on the casing, triggering an alarm, e.g. an existing burglar alarm.