Hardy HI 4050, User Manual

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100 Chapter 5
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Make sure that nothing is draped over the scale/vessel or the load cell, such as a hose,
electrical cord, tubes, or other objects.
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Check to see that nothing comes in contact with the scale/vessel other than service wires
and piping that have been properly mounted with flexible connectors.
Electrical Check Procedures
Check to see that there is power to the Weight Controller.
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If there is power to the controller the front panel display should be lit.
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If the display appears with a value the unit is ready for calibration.
The 4050 supplies 5 VDC excitation to as many as eight 350 ohm load cells/points, and the
expected output from each load cell/point depends on the mV/V rating of the load cell/point
and weight.
Typical Load Cell/Point Input/Output Measurements (EXC & SIG outputs)
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A 2 mV/V load cell/point will respond with a maximum of 10 mVDC at full
weight capacity where the system includes the weight of the vessel and the weight
of the product as measured by the load cell/point.
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If the load cell/point weight capacity is rated at 1000 pounds, the load cell/point
output will be10 mVDC at 1000 pounds, 7.5 mVDC at 750 pounds, 5 mVDC at
500 pounds and so on.
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A zero reference point will vary from system to system depending on the “Dead
Load” (weight of the vessel and appurtenances only, with no product loaded) of
the vessel. The example below uses a dead load of 500 lbs.
250 500 750 1000
10
9
8
7
6
5
4
3
2
1
WEIGHT IN POUNDS
M
IL
LIV
O
LTS D
C
DEAD LOAD 500#
ZERO REFERENCE POINT
MAXIMUM LOAD CAPACITY