Guralp Systems CMG-5T User Manual

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CMG-5T

digitizer should be double this: 693,944 counts. All Güralp

Systems sensors use balanced differential outputs.

The actual signal at the digitizer of 701,512 counts is within
1.5% of this value, indicating that the sensor is adequately

calibrated.

10. If you know the local value of g, you can also perform absolute

calibration by tilting the sensor by 90 ° and varying the

calibration signal until it precisely compensates for the signal
generated due to gravity.

11. Calibrate any other sensors connected to the digitizer in the

same way. You must wait for the previous calibration to finish
before doing this: clicking Inject now has no effect whilst the
Calibration enable relay is open.

If you prefer, you can inject your own signals into the system at any

point (together with a Calibration enable signal, if required) to provide
independent measurements, and to check that the voltages around the

calibration loop are consistent. For reference, a DM24-series digitizer
will generate a calibration signal of around 16000 counts / 4 V when

set to 100% (sine-wave or step), and around 10000 counts / 2.5 V when
set to 50%.

Issue E