Adam Equipment CBK 6M, Руководство по обслуживанию

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The load cell can be tested while it is connected to the A/D converter circuit board, using
the scale power supply for excitation voltage.
TESTING LOAD CELLS IN THE SCALE
The signal from the load cells is amplified by the circuits on the A/D circuit board. The
signal needs to be amplified to make it acceptable for the A/D converter used. The CBK-M
scales amplify the input by 200 and change the no load voltage to about +2.5V. The
amplified and offset voltage is measured at pin 6 of IC7, the INA118P amplifier IC. This
voltage is sent to the filter and then to the A/D converter.
7.0 CALIBRATION
The CBK-M Scales are sealed to prevent unauthorised calibration.
The calibration of the CBK-M scale is
accomplished by removing the label at
the base of the scale which covers a hole
through which the PCB can be accessed.
If your scale is not provided with this
hole, you need to break the security
seals and remove the top cover to gain
access to the circuit boards inside. See
the figure on the security seal below.
WARNING: CALIBRATION OF THE CBK-M SCALE MAY MAKE IT ILLEGAL TO USE
THE SCALE FOR SOME APPROVED APPLICATIONS. CONTACT YOUR TRADING
STANDARDS OFFICE FOR FURTHER ASSISTANCE.
© Adam Equipment Company 2007
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