What is a disadvantage of measuring vibration with contact sensors?

Measuring vibration with contact sensors involves physically attaching a sensor to the surface of the machine or component being tested. This physical connection can influence the very vibrations being measured, introducing potential inaccuracies. The sensor might dampen or modify the vibration signal due to the mass of the sensor or its attachment method, which can lead to erroneous readings.

This phenomenon occurs because contact sensors may alter the natural response of the structure or be affected by the mounting method, creating additional stiffness or mass that can skew the results. Thus, while contact sensors can provide reliable data, their impact on the vibration dynamics can be a significant disadvantage in certain applications.

In contrast, the other options do not align with inherent challenges posed by contact sensors: they may indeed provide accurate readings under ideal conditions, their durability can vary depending on the context, and they may not necessarily have noise sensitivity advantages compared to non-contact sensors.