Siemens Milltronics BW500 Operating Lnstructions page 66

Example:
A non-linearity with respect to the ideal response exists in a belt scale application with
design rate of 200 t/h. It is decided to do material tests at 15, 30, 45, 60 and 75% of the
design load. After performing a zero and a span calibration at 100% of the design load,
followed by material tests and manual span adjust, five material tests were performed at
30, 60, 90, 120 and 150 t/h, as indicated by the BW500. The following data was tabulated.
(This example is exaggerated for emphasis).
The material tests should be run at same belt speed, representative of normal operation;
in this case 1.2 m/s. For each rate, record the corresponding load value by scrolling to the
BW500 load display during running conditions or by calculation.
load = rate
BW500 load
kg/m
6.94
13.89
20.83
27.78
34.72
a)
calculation example: % compensation = [(2.5 – 2.8) x 100]/2.8
Page 60 Milltronics BW500 and BW500/L - OPERATING INSTRUCTIONS 7ML19985DK05
speed
material test
tonnes
2.5
5.0
7.5
10.0
12.5
BW500 total
compensation
tonnes
2.8
4.5
7.9
9.2
13.3
a)
%
-10.7
11.1
-5.1
8.7
-6.0