Rice Lake Challenger 3 MSI-3460, Техническое руководство

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MSI-3460 Challenger 3
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5.4 Guidelines for Capacity and Resolution
Crane scales are subject to forces that regular floor scales do not see. Bridge cranes, hoist cranes and mobile cranes lack
rigidity and tend to bounce or swing when loads are lifted. Rice Lake Weighing Systems recommends that resolution be kept in
the 1:2000 to 1:3000 range. Some improvement in stability can be achieved by increasing the filtering. If the MSI-3460 display
is unstable, it is recommended that the resolution be reduced and/or filtering increased.
Due to Legal for Trade requirements and general scale design criteria, the weight must be stable for
ZERO , TARE , and TOTAL
to work.
To improve stability:
• Increase the filtering, at the risk of increasing settling time
• Increase the
d (reduce resolution)
• Increase the stable window
The MSI-3460 defaults to ±1d as a stable window. It can be changed at Rice Lake Weighing Systems to a higher value
if desired. Often ±3d is selected for bridge cranes as these tend to have a lot of bounce to them. This will carry an
accuracy penalty, adding ±3 d to the total accuracy of the scale, if the zero or tare operation happens to capture the
weight in a valley or peak.
Setting capacity is dictated primarily by the capability of the load cell. Many different capacities of the MSI-3460 are offered.
Never set the capacity of the scale higher than the rating of the load cell.
Due to excellent linearity of the MSI S-Beam load cell, it is acceptable to set lower capacities to better match the crane that the
MSI-3460 is used on.
Example: if the hoist is rated for 9000 lb, then use a 10000 lb weight and reset the capacity to 9000 lb.
Use the Initial Calibration procedure for this calibration. De-rating as much as 50% of the capacity is usually acceptable, but the
scale may be less stable if the d is decreased.
Due to kg to lb conversions, the capacity of all MSI-3460 systems is rated approximately 20% higher than the rated capacity in
pounds. This is to allow the kg capacity to be exactly 1/2 the number of the pound capacity.
5.5 Constant Calibration (C-Cal)
When adequate test weights are not available, the MSI-3460 can be calibrated using a programmed constant calibration which
is referred to as C-Cal. To use this, the C-Cal number must be known from a previous calibration. Rice Lake Weighing Systems
supplies replacement load cells for the MSI-3460 with the C-Cal value stamped on the serial number label. When a calibration
is performed with test weights, a new C-Cal is generated. C-Cal can be used when the electronics are replaced to get an
approximate calibration that is suitable for non Legal for Trade applications.
The C-Cal number must be known prior to starting this procedure. For an MSI-3460 with its original load cell,
Rice Lake prints this number on the calibration record, the serial number tag, and on the calibration log found
inside the battery compartment.
C-Cal can slightly reduce the absolute accuracy of the system if the electronics are replaced or a new load cell is installed and
is intended for non-critical use only. Legal for Trade installations require that the MSI-3460 is calibrated using test weights.
If a system was originally multi-point calibrated, the C-CAL calibration will erase the additional span points, as C-Cal is only a
two point calibration (zero and span at 10% of capacity).
Use the following steps to perform a C-Cal calibration.
1. Enter Configuration mode ( Section 5.1 on page 17 ).

displays.
2. Press to scroll to

.
3. Press .

displays. Ensure all weight has been removed from the scale.
4. Press to set the zero calibration point. A flashing

displays. If the zero is in range, the scale will display

,
then displays

.
Note
WARNING
IMPORTANT
USER
F
TARE
TARE