Inventors:
Paul J. Murphy - Pittsfield MA
International Classification:
G08B 2100
Abstract:
An elongated hollow body is provided with a mid-length transverse partition and one end of the body is mountable from a sewer pipe in lieu of a cleanout plug thereof and contains a buoyant mercury switch tethered to the partition through the utilization of thin, flexible and relatively insulated conductors passing through the partition in fluid tight sealed engagement therewith and electrically connected to spaced contacts within the mercury switch. The other end of the body on the side of the partition remote from the buoyant mercury switch supports a battery, a momentarily actuatable test switch and an electrically actuated signal generating device, the mercury switch, signal generating device and battery being electrically connected in a loop-type circuit. A bypass circuit is provided for bypassing the mercury switch and the test switch is serially connected in the bypass circuit.