4294 加速度計(jì)校準(zhǔn)器,手持式,電池供電
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.
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).
Use of the calibrator is very straightforward. The transducer is conveniently attached to the calibrator table using a 10–32 UNF Steel Stud (YQ 2963). Alternatively, the 10 g Mounting Disc (DB 2996) supplied, provides a convenient means of attaching transducers manufactured with 3 mm threads or those fitted with Mounting Magnet UA 0642. The mounting disc also permits the attachment of transducers with either beeswax or cyanoacrylate adhesive.
The calibrator is actuated by pressing the small button on the side of its housing. Following system adjustment, the calibrator is switched off by pressing the button a second time. To prolong the useful life of its built-in battery, Type 4294 automatically switches off after approximately 100 seconds.