5 overview and equipment required, 6 trimming individual cells – Rice Lake Truck Scales User Manual
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Survivor
®
SR Siderail Truck Scale Assembly Instrucitons
8.5
Overview and Equipment Required
Load Cell Trimming
Individual load cell signal trimming (equalizing the signal output from each load cell) must be done first along
each side of the scale so all cells on a side have equal signal output. Adjustments are somewhat interactive, so each
side should be done at least twice.
Once that is done, load cell pairs—one from each side—are trimmed as paired sections until each sectional output
is equal. Adjustments to each section should also be done at least twice.
Figure 8-4. Load Cell Trimming Diagram.
Equipment Required
Both of these trimming operations can be done using only a weight cart parked in various locations on the scale.
Final verification of equal output trimming, however, will require test weights to be placed on the deck in various
locations.
8.6
Trimming Individual Cells
Connect all load cells to the summing board terminals in the junction box, and connect the main interface cable
from the junction box to the indicator. Power up the indicator.
Turn all load cell potentiometers (individual and section) in the junction box clockwise until a clicking noise is
heard when you continue turning. This eliminates any initial resistance so all signals are at full strength. You’re
now ready to do individual signal trimming.(See j-box summing box instructions for details)
Side 1
The first objective is to adjust individual load cells along one side of the scale for equal signal output when equal
weight is put on those cells. For convenience, that side of the scale will be referred to as Side 1. The trimming
weight you will use will be the loaded weight cart.
1. Park the cart as close as possible to Side 1 being trimmed with the wheels centered over the end load cell
mount (No. 1 in Figure 8-1). Record the indicator reading. Remember that the scale is still uncalibrated, so
the indicator readings are simply raw counts rather than weight units.
Figure 8-5. Trimming Load Cell Number One
2. Move the cart directly over mount No. 2 and record that reading. Move the cart directly over mount No. 3
and record that reading. Move the cart so the wheels are centered directly over mount No. 4 (you may have
to turn the weight cart around so all wheels remain on the scale) and record the reading.
1st – Trim Side 1 Cells (1, 2, 3, 4)
2nd – Trim Side 2 Cells (5, 6, 7, 8)
3rd – Trim Sections
(1,8; 2,7; 3,6; 4,5)
Weight
Cart
1
4
3
2
8
5
6
7
1
4
3
2
8
5
6
7