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

Operator's Guide
1 Introduction
The CMG-5T accelerometer is a three-axis strong-motion force-
feedback accelerometer in a sealed case. The sensor system is self-
contained except for its 10 – 36V power supply, which can be
provided through the same cable as the analogue data. An internal
DC–DC converter ensures that the sensor is completely isolated.
The 5T 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 whole dynamic range two
separate outputs are provided, one with high gain and one with low
gain. Nominally, the high gain outputs are set to output a signal 10
times stronger than that from the low gain outputs.
The 5T 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 unit to output 5 V single-
ended output for 1 g (≈ 9.81 ms -2 ) input acceleration. The standard
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