Chapter 1. Introduction

This document provides a detailed example of how to use the triggering subsystem of Platinum firmware for CMG-EAMs and CMG-NAMs. It also applies to integrated instruments and data acquisition systems incorporating modular EAMs, such as the CMG-5TDE networked accelerometer.

The example involves an EAM receiving data from two instruments. We will configure:

• a level trigger on sensor A, Z component at 2.0 gal;

• a level trigger on sensor B, Z component at 2.0 gal; and

• the trigger matrix to record an event when both level triggers fire.

When a trigger occurs, we will compute:

• individual PGAs for the Z, N and E components;

• a two-dimensional resultant PG for the horizontal components, N and E, of each sensor;

• a three-dimensional resultant PG for all components, Z, N and E, of each sensor;

• the IJMA of all components of both sensors;

• an FFT of all components of both sensors; and

• the predominant frequencies from the FFT computed above.

The trigger summary configuration will include all five PGA values and the IJMA value.

Many other configurations are possible and it is hoped that this example will make clear the techniques required to build configurations to your own requirements.

The screen-shots are taken from a system running Platinum build 11205. Earlier builds do not include sufficient functionality. Later builds may show more options or minor differences in screen layout; the underlying principles remain the same.