New Accelerometer for Very Low Level Testing

Brüel & Kjær (UK) has launched a new DeltaShear® Accelerometer - Type 8344 - suitable for measuring very low level vibration effects in structures and machines.

The 8344 combines very high sensitivity with excellent frequency response, making it ideal for measurement and analysis applications where a very low level of vibration can affect performance. This would include the effect of ground-borne vibration - caused by construction site operations - on nearby installations, containing devices such as electron microscopes or semiconductor wafer manufacturing facilities.

The 8344 has a built-in DeltaTron preamplifier, which allows it to form part of a Fast Fourier Transform (FFT) testing kit, when coupled with Brüel & Kjær’s 2250 sound level meter and FFT data analysis software.

The 8344 is a piezoelectric DeltaShear® accelerometer with integral electronics, which can be mounted on a test object with a M5 threaded steel stud. The transducer is hermetically sealed, with a Transducer Electronic Data Sheet (TEDS) containing sensor - and application - specific information, including frequency response compensation. It has an incredibly robust, stainless steel exterior and operates with temperatures ranging from –50 to +100°C.

The DeltaShear design involves three piezoelectric elements and three masses arranged in a triangle around a triangular centre post, which is bolted to the housing. The ring pre-stresses the piezoelectric elements to give a high degree of linearity. The signal is collected between the housing and the clamping ring and then amplified by the built-in DeltaTron preamplifier.