Electronic speed switch is best suited to monitor any rotational or transitional repetitive motion. This switch is suitable for the speed monitoring of critical elements of any material handling system, such as belt/screw conveyors, elevators, crushers, drag chains, rotary feeders, etc. The electronic speed switch detects the under speed/ over speed conditions in the system by no contact method and offers output contacts for protection control and interlock purposes. Different applications of the speed switch include: detection of jamming in feeders, sequential interlocking of conveyor, detection of blade breakage in reclaimer chain, motion detection and fan speed monitoring. Some of its models containing indication facility or having 4-20 ma output are extensively used in central control room instrumentation. Other models with multiple setting facilities are applied in speed dependent switching of control gear. The speed switches are equipped with a sensor probe and a monitor unit. While the sensor probe is non-contact type inductive sensor that picks up speed information from the system, the monitor unit receives this information, evaluates it and supplies necessary output. The epoxy potted probe is dustproof and water-tight to ip-67, and the monitor, in sheet steel or cast aluminium, epoxy painted housing, is dust-tight to ip-55. The various advantages of the speed switches include non-contact sensing; possibility of extreme low speed detection; built-in initial bypass facility and matching speed indication is also possible.
