Accelerometer Mounting For an accelerometer to accurately sense and generate useful data, it must be properly coupled to the test object. This requires that the accelerometer mounting be rigid over the frequency range of interest. The methods for mounting an accelerometer usually depend on the accelerometer and the test structure. A selection of studs, isolated mounting pads, wax, industrial magnets, and triaxial cubes are available from Kistler to solve virtually any mounting/installation problem. Some industrial accelerometers have an electrically isolated mounting surface which provides electrical (ground) isolation between the sensor signal ground and the mounting surface. A designated mounting torque provides the proper coupling force between the accelerometer and the test object without overstressing and distorting the accelerometer mounting base. Always use the proper sockets and torque for each Kistler accelerometer as listed on the individually supplied calibration certificates. Top-mounted connector. Tape or clamp to relieve stress on connector Adhesive mounting This simple method is ideal for mounting where drilling holes is not practical or where the mounting surface is not flat. Direct Adhesive Mounting Many lightweight accelerometers are designed strictly for adhesive mounting. When properly mounted, these units will provide accurate data within the specified frequency range. This method is ideal for modal and structural analysis where the test structure cannot be modified for mounting the accelerometers. For measurements up to 5 kHz, wax mounting is a suitable adhesive. Isolated, Adhesive Pad Mounting Hard anodized aluminium mounting pads offer several advantages when the accelerometer must be mounted to irregular surfaces or when ground isolation is required. These pads are adhesively mounted to the test structure providing a flat mounting surface and a high quality mounting thread. The hard anodized surface provides ground isolation between the sensor and the mounting surface. This is particularly useful in preventing ground loops. Tape or clamp to relieve stress on connector (about 21/2 to 3 inches from connector) Stud mounting The best method for mounting an accelerometer is with a threaded stud. Most Kistler mounting studs are machined from Beryllium Copper for high strength and low modulus of elasticity, coupled with high elastic limits. These studs provide excellent coupling between the accelerometer's mounting surface and the test object. Care should be taken to ensure that the two mounting surfaces mate evenly. The mounting threads must be perpendicular to the surface and free of any burrs. The surface must also be flat to ensure good coupling. Adding a slight amount of grease or oil between the mounting surfaces improves the coupling, especially at higher frequencies. Side-mounted connector. www.kistler.com 11