Rion DA-20 Instruction Manual page 95

Recording a calibration signal
Calibration for recorded data is normally performed by recording the
sensor calibration signal before or after the data recording procedure and
by correlating the result to the recorded data.
This method allows correct calibration even if the effect of the confi guration
elements of the sensor (extension cable, preamplifi er, etc.) is unknown.
In principle, it will be necessary to record the calibration signal again when
the confi guration elements have been changed. Input range information
will also be required (if range switching is possible).
In the representative examples listed below, recording the calibration signal
is necessary. In actual use, the operator should decide whether calibration
is necessary, based on information given in this manual and other data.
1. Sensor input range setting (not input range setting of DA-20) was
changed. In this case, the same measurement quantity input may
result in a different output signal being supplied to the DA-20.
2. Extension cable was changed (length, cable gauge, etc.)
A change in electrical impedance may result in a different output
signal being supplied to the DA-20.
3. Other cases
Recording
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