Guralp Systems CMG-DM24S12AMS - Manual (Page 65)

CMG-DM24S12AMS Operator's guide
5U unit's power supply; its filtered outputs provide the ±12 V required
to operate the sensor electronics. The DC–DC converter is protected
against polarity reversal.
The calibration signal and calibration enable inputs are referenced to the
signal ground. These lines can be connected directly to the
DM24S12AMS's calibration lines.
5.3 Calibrating CMG-5U sensors
The 5U accelerometer is supplied with a comprehensive calibration
document, and it should not normally be necessary to calibrate it
yourself. However, you may need to check that the response and output
signal levels of the sensor are consistent with the values given in the
calibration document.
Absolute calibration
The sensor's response (in V/m/s
2
) is measured at the production stage by
tilting the sensor through 90 ° and measuring the acceleration due to
gravity. Local g at the Güralp Systems production facility is known to an
accuracy of 5 digits.
Relative calibration
In addition to the response of the sensor, several other variables are
calibrated at the production stage. Using these values, you can convert
directly from counts (as measured in Scream!) to acceleration values and
back. You can check any of these values by performing calibration
experiments.
Güralp sensors are calibrated as follows:
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