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5.2 Adjustment / calibration of the amplifier
In order to adjust or calibrate the amplifier a multimeter has to be connected to the analogue output.
Inspection:
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Unload the measuring device.
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Connect the multimeter (refer to chapter 4 “Terminal Assignment”).
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Set the analogue output to 0 Volts resp. 4 mA.
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Load the measuring device (i.e. the transducer) at least 3 times with its maximum load.
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Load the device with 80 % of its maximum load.
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Check if the analogue outputs comply with the load and is in the designated specs.
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If not, the measurement system might need to be recalibrated. Above that, the installation
position and the overall setup might need an inspection.
Adjustment / Calibration:
The coarse amplification, and thus the voltage output, is determined by an internal resistor (RG) and
can be fine adjusted by a potentiometer (P-02). To adjust the current output, which follows the voltage
output, the potentiometer P-03 is to be used. (See next chapter.)
Before the calibration a warm-up time of approx. 30 mins should be kept. The measuring device has to
be unloaded.
Unloaded means with:
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Force transducers:
no applied force at all
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Pressure transducers
no pressure, except atmospheric influence
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In this unloaded state adjust the zero-point with the potentiometer P-01.
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Apply a defined load. (by calibrated weights, pressure generator etc.)
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Adjust the analogue output corresponding to the applied load.
In order to reach the required accuracy, it may be necessary to repeat these steps.
