Tag: Vibration Sensors

  • 24.4 Mechanical vibration switches

    A much simpler alternative to continuous vibration sensors (displacement or acceleration) and monitoring equipment suitable for less critical applications is a simple mechanical switch actuated by a machine’s vibration. These switches cannot, of course, quantitatively analyze machine vibrations, but they do serve as qualitative indicators of gross vibration. The following photograph shows a Robertshaw “Vibraswitch”…

  • 24.3 Vibration Monitoring hardware

    The following photograph shows a large air blower in a wastewater treatment facility equipped with a Bently-Nevada model 3300 vibration monitoring rack (located left-center on the foreground panel): Five vibration measurement and display cards are installed in this rack, each card capable of processing up to two displacement sensor signals. A six-channel temperature monitor card…

  • 24.2 Vibration sensors

    Sensors used to measure vibration come in three basic types: displacement, velocity, and acceleration. Displacement sensors measure changes in distance between a machine’s rotating element and its stationary housing (frame). Displacement sensors come in the form of a probe that threads into a hole drilled and tapped in the machine’s frame, just above the surface of a rotating…

  • Chapter 24 Machine vibration measurement

    Unlike most process measurements, the measurement of a rotating machine’s vibration is primarily for the benefit of the process equipment rather than the process itself. Vibration monitoring on an ammonia vapor compressor, for instance, may very well be useful in extending the operating life of the compressor, but it offers little benefit to the control of the…