SV SLA-PA201, Manual

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adjust gain if the signal is low. To use AutoRange function is more desirable than hand-operated
adjustment.
[AutoRange] calculates input signal and automatically adjusts gain. So it would be better to
accomplish AutoRange before calibration. [Fig. III-5-3] shows AutoRange process.
HighTech
1
RealWave H/W has an analog gain with 10 times, but digital gain is used at gain
adjustment. Analog amplifier accomplishes the role of Pre-Amplifier. Work of the
analog amplifier depends on the cable connected to the sensor.
Digital gain usually uses the method that multiplies an original signal by any gain,
but it also amplifies noise with signal. So this system doesn’t use the method.
This system uses the 24bits for ADC(Analog to Digital Convert) and 16bits data
is extracted from 24bits data. Therefore, the Digital Gain means to extract data
shifting bit position as figure below when extracting 16bits data from 24bits data.
Unlike conventional method using fixed magnification, It is very effective to
amplify signal without the amplification of noise.
5. 3 Calibration
After selecting type of transducer and entering sensitivity and adjust gain, click [Calibrate] button.
A graph window will appear like [Fig. III-5-5]. It is only the status to display data in real-time without
measurement. By clicking [Start] button, it is calibrated during 10 seconds. After calibration, [Fig. III-
5-6] will appear and the result is calculated by compensated gain.
Generally, calibrated sensitivity can be calculated as follows:
Compensated Sensitivity = Compensated Gain
×
Inputted Sensitivity <Eq. III-5-1>
If it is calibrated inadequately, you can return to the pre-calibrate status by clicking [1.0] button. In
case calibrated gain value is smaller than 0.5 or exceeds 1.5, an alarm message will be pop up and the
transducer cable or the power of calibrator need to be checked.