CALIBRATION
GENERAL
As belt and material load can vary with temperature and humidity, frequent calibration may be required to
maintain system accuracy. A calibration should only be performed after the belt has been run as long as
practical, and is sufficiently limber.
When the CompuScale III is first commissioned, several Zero and Span calibrations are normally performed to
verify the calibration results are repeatable.
A Zero or Span calibration (in progress) may be aborted by .
Should the belt speed fall below 5% of the design Belt Speed (P4) value, while
a calibration is in progress, [SPEED < 5%; CALIB ABORTED] is displayed.
The CompuScale III calibration display is divided into the following fields:
INITIAL CALIBRATION REFERENCES
The first calibration performed, establishes the Initial Zero and Initial Span calibration references. Subsequent
Zero and Span calibration results are compared to these references. The maximum acceptable deviation
between an Initial Calibration Reference and a subsequent calibration result is 12.0% of span. Otherwise,
[ZERO OUT OF RANGE] or [SPAN OUT OF RANGE] is displayed in the AUX 2 field.
While a calibration in progress is establishing an initial calibration reference, the dynamic count value is
displayed. Otherwise, the dynamic load value is displayed.
The initial calibration references may be reset. Refer to Parameters/P77 Initial Zero Reset and P88 Initial
Span Reset. Both initial calibration references (along with all other programming) are erased by a Reset (P99).
150%
100%
RATE
0%
-50%
BELT REV.
UNITS
RATE BAR
GRAPH
MULTISPAN
TYPE
VALUE
ECAL
CALIB.
AUX 2
AUX 1
PL-367
6 – 1
