Shock and Impact Sensors Information
Shock and impact sensors are a subset of accelerometers. They are used for measuring, displaying and analyzing shock and impact. Device type is one of the most important specifications to consider when selecting shock and impact sensors. Choices include raw sensors or more complex transducers, switches that make or break contact when a certain activation or vibration level is achieved, and gauges or indicators that have a display but no electronic output. Choices also include instruments, meters, recorders and totalizers. Instruments, meters and analyzers are self-contained shock and impact sensors which usually have a local output. They may also provide signal processing or conditioning. Recorders and totalizers record measure shock and impact values and accumulate totals.
Shock and impact sensors provide outputs that are function of acceleration, velocity, displacement or temperature. Performance specifications include maximum shock, maximum vibration, and maximum acceleration. Frequency range, minimum accuracy and number of axes are also important considerations. As a rule, shock and impact sensors that do not have integrated sensors do not have a rated acceleration value. To minimize frequency-response errors, cables can be attached to same machine to which shock and impact sensors are attached. With regard to the number of axes, single-axis, biaxial and triaxial products are commonly available. Biaxial and triaxial shock and impact sensors usually provide measurements along orthogonal axes. In the case of triaxial sensors, these axes are specified as X, Y and Z.
Sensor-Mounting Styles
There are three sensor-mounting styles for shock and impact sensors: adhesive base, magnetic base, and stud or bolt-on. Products with an adhesive base are designed to be glued or epoxied to a machine’s surface. Sensors with a magnetic base are designed for use with metal surfaces. Stud-mounting is probably the most secure mounting method. Shock and impact sensors with a threaded section can be fastened securely to the machine being monitored. Some applications require shock and impact sensors to be mounted on an electrically-isolated surface to provide ground isolation between the mounting surface and signals from the device. Triaxial mounting cubes can also be purchased to mount three sensors together in an orthogonal configuration to each other. In this way, only one mounting surface on the monitored device has to be used for all three.
