Abstract: A lighted switch set gauge includes Hall effect devices using a circuit activating switch attached to a lower extension of indicating and switch set pointers. The switch set pointer is externally adjustable. An overriding slip gear with automatic spring-back is incorporated in the switch set arm prevent damage to the set pointer at the extreme ends of its range of movement. The indicating pointer can be calibrated without removing a hub attached to the shaft of the gauge meter movement.

Abstract: An adjustable signalling gauge may utilize a non-captivating, magnetically actuated switch element which is mounted in an influence zone of the path of a magnet carried by an indicating pointer of a gauge. The gauge may be easily adjusted by an indirect adjustment mechanism. The adjustment may be by a reducing gear. Indirect adjustment effectively allows a reduction in the torque required to change the switching threshold.

Abstract: A signalling gauge may utilize a non-captivating, magnetically actuated switch element which is mounted in an influence zone of a path of a magnet carried by an indicating pointer of the gauge. The gauge may operate despite the presence of dust, dirt or other pollutants for an extended period of time without inducing sparks or arcing often associated with electromechanical contacts. Hall effect switch elements such as latches or digital switches may be utilized as a switch element for signalling to drive an audio or visual alarm or a digital signal.

Abstract: A self-cleaning or wiping switch contact for use on machinery monitoring gages embodies a spring contact arm mounted directly on the gage movable pointer for wiping coaction with either high or low adjustable set contacts of the gage.