Fiber Optics permit Design Innovations in Optical Meter-Relay with True Proportioning Action

The new optical meter-relay is not only one of the simplest devices now available for automatic control functions, but like all meter-relays, it has the further advantages of reliability and easy adjustment of set points. It also has continuous signal indication, whether or not a set point has been passed. From a design standpoint, the new device is noteworthy because it is built around a combination, used for the first time in controlling instruments, of fiber optics, a reflecting disc, and solid-state circuitry. Inherently fail-safe, it is a complete departure from previous designs.