Glossary

Vibration
concepts.

One motion, four ways of looking at it. Each page is a short walkthrough of a quantity you will meet on a monitoring unit and in a compliance limit.

Concept

How the ground moves

Four short pages with a moving picture on each, then a real record read with those ideas.

x · mm

How far the ground moved from rest — usually a fraction of a millimetre.

v · mm/s

How fast the ground is moving at each instant. Compliance limits are written in mm/s.

a · g

How fast the velocity is changing. This is what a ViB accelerometer senses.

f · Hz

How many cycles a second. The same travel is a different speed and a different g at a different rate.

A real blast is many tones at once, so the trace is messy. The pure tone is the building block, so you can check the sums.