Guralp Systems CMG-5T Compact - Manual (Page 3)

Operator's Guide
1 Introduction
The CMG-5T Compact is a three-axis, strong-motion, force-feedback
accelerometer in a sealed case. The accelerometer is self-contained
except for its 10 – 36V power supply, which can be provided through the
same cable that carries the analogue data. An internal DC–DC converter
ensures that the sensor is completely electrically isolated. Optionally,
this converter can be omitted, in which case an external ±12 Volt DC
three-way or 'dual rail' power supply is required. Sensors with this
option have substantially lower power requirements than those fitted
with the DC–DC converter.
The 5T Compact system combines low-noise components with high
feedback loop gain to provide a linear, precision transducer with a very
large dynamic range. In order to exploit the entire dynamic range, two
separate outputs - high and low gain - are provided. Nominally, the high
gain outputs are set to output a signal 10 times stronger than the low
gain outputs.
The 5T Compact sensor outputs are all differential with an output
impedance of 47 Ω. A single signal ground line is provided as a return
line for all the sensor outputs.
Full-scale low-gain sensitivity is available from 4.0g down to 0.1g. The
most common configuration is for the 5T Compact unit to output 5 V
May 2011 3