Hardy HI 4050, User Manual

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Calibration 101
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Based on this example, the operating range for this scale is 5-10 mVDC with a 500 pound
weight. Understand that after zeroing the instrument the 0 reading on the instrument refers
to the zero reference point and not absolute 0 mVDC or absolute 0 weight.
NOTE Load cell/point measurements can be checked with a digital voltmeter at the J1 connector
on the rear panel or at the summing box of the HI 4050 or use Integrated Technician if you
are using the IT Junction Box.
Allow the instrument to warm up for about 15 minutes before doing the calibration
procedures. Mechanically exercise the scale using maximum load several times before final
calibration.
Calibration Procedures
C2 Calibration
C2 Electronic Calibration calibrates a scale system electronically without using certified
test weights. It uses up to eight load sensors, a junction box, interconnect cable and an
instrument with C2 capabilities, such as the HI 4050 Weight Controller. Digital information
within an HI C2-certified load sensor details its unique performance characteristics. The HI
4050 Weight Controller reads the performance characteristics of each load sensor and
detects the number of load sensors in the system.
Before running C2 calibration, run all of the pre-calibration procedures. Make sure you
have configured the HI 4050. This includes setting the units, decimal point, scale capacity,
averages etc. For instructions please see Chapter 4, Configuration.
Reference Weight
Reference Weight is the total live load that is currently on the scale. The calibration process
uses a reference weight, which is normally zero (no weight on the scale), but can be any
known weight on the scale. With nothing on the scale, the Reference Weight is 0.00. With
5 lbs on the scale, the Reference Weight is 5.00 lbs.
Gravitation Correction
Objects weigh about 0.5% less at the equator than they weigh at each pole because the force
of gravity is less at the equator than at the poles. For example an object weighing 100
pounds at the North Pole on a spring scale would weigh 99.65 pounds at the equator.
Depending on the latitude of your location, your scales would measure somewhere in
between. The table below shows the gravitation correction factor for various cities around
the world.
In general if your location is between the 45th parallel and the equator, gravity correction
is greater than 1.0. For example, at these latitudes, because the gravity is less, you are
adding, 1.0006 for an error that is .06%). For locations between the 45th parallel and the
North or South Pole your correction factor will be less than 1.0. For example .9994 for an
error that is -.06%.