Accelerometer calibrator
0 – 70 g | Type 4294 Bruel and Kjaer

Type 4294 permits accurate adjustment of measuring instrumentation at a standard acceleration level of 10 ms–2 (0 – 70 g load). The reference signal may additionally be used for velocity and displacement calibration, at 10 mms–1 and 10 µm respectively.
Type 4294-002 permits accurate adjustment of measuring instrumentation at a standard acceleration level of 3.16 ms–2 (0 – 200 g load). The reference signal may additionally be used for velocity and displacement calibration, at 3.16 mms–1 and 3.16 µm respectively.

The calibrator embodies an electromagnetic exciter driven by a crystal oscillator at a frequency of 159.15 Hz (1000 rad s–1). Servo feedback via a small accelerometer on the underside of the vibration table is used to maintain a constant and accurate vibration level independent of the mass of the transducer under test (70 g for Type 4294 and 200 g for Type 4294-002).

To prevent overload, power for the calibrator is automatically disconnected if a transducer mass above a certain level is mounted on the table (70 g for Type 4294 and 200 g for Type 4294-002).