Sterling Scale XC880A - Manual (Page 54)

XC880A OWNERS MANUAL
1. Press ‘6’ followed by the ‘PARM’ key. The current Analog Output
setting is displayed.
2. Press ‘SCALE SELECT’ until desired setting is displayed. Choices
are:
AO OFF Analog Output Disabled
AO GROSS Output Follows Gross Weight.
AO NET Output Follows Net Weight.
AO CAL Output Follows Calibration Data.
3. Press ‘ENTER’. The analog output will now be updated using the
selected Data. Perform a calibration check/adjustment as described
in section 10.3.3.
10.3.3 Analog Output Calibration
Below is the procedure for calibrating the analog output to match
the weight. This procedure requires an ammeter set to a range greater
than 20mA, a known test weight of at least 10% of scale capacity, and a
small flat screwdriver to adjust the potentiometers.
1. To verify scale accuracy, place the test weight on the scale and
observe the display. If the displayed weight does not match the
actual weight, calibrate the scale as described in section 4.2.1.
2. Turn off power to the unit, remove the front bezel and connect the
ammeter leads across the 4-20mA output.
3. Locate the output type selection jumper J5, and ensure jumper is in
position marked ‘I’ for current output.
4. Power the unit. Remove weight from the scale and press ZERO.
Observe the reading on ammeter. If the reading is exactly 4.00mA,
go to step 6.
5. If the reading is not 4mA, adjust the ‘zero’ potentiometer marked R8
until the reading is 4.00mA.
6. Load test weight onto the scale. Calculate Iout using this simple
formula: Iout(mA) = ((Test Weight / Scale Capacity) x 16) + 4.
7. Adjust the ‘span’ potentiometer marked R7 until the reading on the
ammeter matches the calculated Iout.
8. Remove test weight from scale and press ZERO. Observe the
reading on the ammeter. If it does not read 4.00mA, repeat steps 4 –
7 until both the zero, and span values are adjusted.
9. Disconnect power, remove ammeter, and place jumper J5 in ‘V’
position for 0–10V output or leave in the ‘I’ position for 4-20mA.
Connect wires from PLC or other device to proper pins on the output
connector, and replace front bezel.
10.4 Remote Scoreboard Display
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