Infrastructure

Meggitt offers a variety of sensors to test and monitor the health of critical infrastructures and facilities for safety monitoring and adherence. Endevco accelerometers are chosen for the combination of high resolution, broad frequency response, protection from the environment, and high stability to contribute to superb systems designs.

TYPICAL APPLICATIONSREPRESENTATIVE MODELS
Seismic measurements86, 87
Scale model modal testingF3/Z602WA, F10/Z820WA, 41A, 42A
Structural monitoring7703A, 41A, 42A, 43A, 45A, 46A
Material studiesF4/Z820WA, F5B/Z11

Application considerations

Seismic measurements

As naturally-occurring or induced seismic applications are typically characterized as motion or low frequency vibration, they usually require a specialized low noise, high resolution accelerometer. When selecting which accelerometer best meets your needs, it is a good idea to keep in mind that the largest g level recorded by an earthquake was 3 g’s in the south island of New Zealand.  Consequently, if you are unsure as to what you expect to record, it might be prudent to choose a ±5 g accelerometer like the Model 87-1.  Alternatively, if you are monitoring an area where very low g levels of activity have occurred, you may want to use the Model 86 with a range of ±0.5 g’s.

Scale model modal testing

Modal testing is performed upon scale models in order to understand their vibration characteristics. To do this, a shaker excites the structure with a known frequency and amplitude while accelerometers mounted at various places on the structure collect data.  The stud mounted F3/Z602WA and F10/Z820WA shakers each have a frequency range of 5 to 2000 HZ but their underlying technologies differ.  The former is an electromagnetic device and the latter a reaction type.  Both the 41A and the 42A are lightweight, IEPE , TEDS capable accelerometers with the former having a top connector and the latter a side connector.

Structural monitoring

Structural Health Monitoring (SHM) seeks to avoid high cost of repairs and injuries to humans and other animals by identifying and monitoring damaging events as they occur. Depending on the structure, this may  require special accelerometers.  Examples include: surviving at high temperatures and radiation exposure (7703A), hermetic sealing against contaminants while maintaining TEDS compliance (41A19-5), or measurement in 3 axis (45A).  For those more general applications, the 43A is a good choice as its unique cube shape allows the sensor to be mounted in two different orientations.

Related topics

DC bias output voltage specification on ISOTRON accelerometers

Understanding IEPE Accelerometer Dynamic Range

Using Resistance Measurements to Test and Verify IEPE Accelerometers

Sensor features that may be critical in infrastructure design testing

  • Ultra low frequency, ultra low noise measurements
  • High sensitivity sensors
  • Precise structural excitation devices