Adam Equipment MCW, Service Manual

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11
Adam Equipment Company Ltd 2012
Before calibrating the scale, you should ensure that you have a suitable
known qualified weight for calibration.
1. When in normal weighing mode with the scale at zero press and hold
down the [TARE] and [ON / OFF] keys to enter the calibration mode.
2. If the calibration switch is in the off position on the main PCB inside the
scale, the indicator will show “CAL OFF” and then exit this mode, if so
remove the rear cover of the Indicator and place the jumper in the “ON”
position. If the indicator shows “CAL-?”, the scale is ready for calibration.
3. When the indicator shows “CAL-?”, press the [TARE] key to confirm and
go to next step.
4. When ‘0.0’ is displayed the scale will begin to calibrate the scale’s zero-
point. Ensure that there is no load or weight on the scale’s platform. Press
the [TARE] key to confirm.
5. A few seconds after the [TARE] key has been pressed in step 4 the scale
will show “300.0” and the kg LED will be illuminated, or “600.0” and the lb
LED will be illuminated depending on which unit you have chosen, this is
the default calibration weight from the factory. Press the [UNIT] key to
select the calibration weight unit that you want to calibrate in. Press the
[Print/Hold] key to choose a different calibration weight value (50kg,
100kg, 150kg, 200kg, 250kg, 300kg or 100lb, 200lb, 300lb, 400lb, 500lb,
600lb); Then put on the weight that you selected and press the [TARE]
key to confirm the chosen standard weight that was selected. The
displayed data will flash on the display and if the scale accepts the
calibration data it will calculate and store the information into the
EEPROM. If an error has occurred, the scale will display “CAL. Er” and
return back to step 4 for re-calibration. If the loaded weight is not within
the range of 95% to 105% of the weight value you selected the scale will
not calibrate but display “CAL. Er” and return back to step 4 for re-
calibration. )
6. If zero cannot be calibrated at step 4 the ADC needs to be checked and
possibly adjusted. Press and hold the [ON/OFF] and [PRINT/HOLD] keys
for three seconds after powering up. The display should show “code” then
the raw ADC counts. The potentiometer VR1 can be adjusted until the
counts with no load are between 20,000 and 30,000. For a working unit
the ADC counts should increment approx 35,000 for a 50kg calibration
mass loaded. VR1 is situated on the main PCB, please see below
diagram.
7.0 CALIBRATION FOR L MODELS