Choosing your accelerometer.

How to decide which accelerometer is right for your application, the following points may help you decide.

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1. What input does your measuring system have? If you can accept pico-coulombs and milli-volts then you are free to choose any accelerometer. If however you do not have or wish to buy a charge amplifier, to allow you to measure the output of a charge type accelerometer then you must choose the IEPE type.

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2. What are you trying to measure – will the mass or weight of the accelerometer change what you are measuring; if it might then you need a low mass accelerometer.

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3. What is the likely acceleration level – if it is very low then you may need a sensitive accelerometer, at least 10pC per g. On the other hand if it is a shock input you will need an accelerometer with a low sensitivity if it is an IEPE type. Remember a shock or hammer blow can have a peak acceleration of at least 2000 g so a 1mV sensitivity in an accelerometer will immediately produces a 2volt output. If you have chosen a 10mV per g sensitivity this will mean 20V output and that may well overload your IEPE input.

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4. Is there an earthing or ground loop problem? If there is then you will need an isolated accelerometer. This can be achieved either by choosing an isolated model or by using an isolating mounting pad.

AP Series Accelerometers

Traditional charge type and also IEPE are available.

Very light weight; as low as 0.14 grams

Very high temperatures as high as 400 degrees C

Very compact triaxial 1cm cubed and only 5 grams in weight

Very affordable!

The AP-Series of miniature accelerometers offers unique characteristics permitting the measurement of acceleration and shock where small size and mass are of prime importance.

The design provides an optimal relation between transducer mass and sensitivity; it combines high shock resistance and good sensitivity in a miniature packaging.

AP-Series is available in a variety of mounting styles suites for a wide range of applications. The titanium alloy housing makes it resistant to mechanical damage and ultra-light.

All transducers are fitted with standard low noise microdot connectors and a flexible thin cable. A calibration certificate is provided with each accelerometer.

Different types provide threaded and adhesive attachments. The sensor body is electrically insulated in some designs and grounded in others.