Gould A134D is a general purpose control relay used in electrical control systems. It contains an electromagnetic coil and one or more sets of contacts that open or close when the coil is energized, allowing a low‑power control signal to switch a higher‑power circuit. Relays like the A134D are often used for logic switching, interlocking, sequencing, and auxiliary control functions in industrial and automation panels. The design provides electrical isolation between the control circuit and the switched load for safer operation. These relays are common in motor control centers, machinery controls, and other applications where electrical control logic is needed.