Adjustments and Calibration
5
3.0
Adjustments and Calibration
The following sections describe adjustments that need to be made to the Summit SB-1000 Bariatric Wheelchair
Scale.
3.1
Mechanical Adjustments
To accommodate minor floor unevenness, the scale feet can be used to adjust scale height up or down a fraction
of an inch. Adjust the feet by hand (lift the scale corner slightly with a pry bar) until all feet are contacting the
floor equally. No jam nuts are supplied for locking the feet, as there is a slight decrease in accuracy when jam
nuts are tightened. However, if you feel that your application requires you to secure the feet, we suggest using
Teflon
®
tape or Loctite
®
.
When adjusting scale feet, use care to prevent the scale foot from bottoming out against the underside of the load
cell. Also, the foot stem can be damaged by bending or stripping threads if extended beyond the maximum height
adjustment.
When height adjustments are complete, recheck level of the deck with a spirit level. The deck must be level
within 1/4".
3.2
Corner Correction & Trimming
The assembled Summit SB-1000 scale is delivered with the junction box corner-trimmed. Corner trimming is
only necessary after replacing a load cell.
To calibrate the scale, the output from each load cell must be matched by adjusting the signals with
potentiometers at the junction box—a process known as trimming.
Remove the junction box cover and identify the correct load cell terminal corresponding to each corner (labeled
CELL 1, CELL 2, and so on). See Figure 8-5 on page 26 for scale deck corner numbering.
The indicator must be connected and calibrated approximately, but it need not indicate the exact weight value. A
test weight is required. The recommended test weight for the SB-1000 is 25% of scale capacity.
With no weight on the scale, zero the indicator. Then turn all four potentiometers (Figure 3-1) clockwise to
increase the reading until a clicking sound is heard from each potentiometer. This ensures the maximum signal
from each load cell.
Figure 3-1. Summing Board Diagram
Teflon
®
and Loctite
®
are both registered trademarks of E.I. DuPont.
Potentiometers
