Valve position indicator

Abstract

An actuator shaft is journaled for rotation within a housing of the apparatus and is coupled to a rotary shaft projecting through the top of a valve or valve actuator. The actuator shaft is coupled to a drum having graphics information on an outer surface thereof, such as the words 'open' and 'closed'. As the actuator shaft rotates the graphics information is also rotated past a window in a window member such that the words observed indicate the position of the valve. The window member couples to an alignment ring which is keyed to receive the window member. By rotating the alignment ring, the window member can be selectively oriented such that the graphics are viewable from a preferred perspective. Each of the components is keyed to be oriented with one another and constrained as a cartridge assembly which can be quickly removed as a single unit to access internal switches and circuitry, whereby the cartridge can be quickly reattached such that the components cannot be inadvertently incorrectly reassembled. An electronic display provides a visual signal indicative of the rotary shaft position and cooperating with the viewable indicia, and further, provides a visual error signal when the valve is in an abnormal position. The apparatus also contains processing means for intelligently controlling internally located control elements, such as solenoids, in response to sensed parameters of the sensed valve.