Berthold LB 442, Operating Manual

Page: 45 / 158

Section 5 Getting Started
43
5.2.4 Calibration
Calibration is carried out in 2 steps.
a) the tare measurement and
b) the actual calibration
a) Tare Measurement
Before starting up the measuring system, the zero or tare weight
has to be determined.
The tare weight changes constantly as a result of conveyor irregu-
larities, such as variation of the thickness of belt or, as in the case
of chain conveyors, differences between chains links and scrapers.
During tare determination, therefore, the conveyor must run and
the average value must be determined over a few complete con-
veyor belt cycles. The rule is: the more cycles, the more precise
the result.
Proceed as follows:
□
Select Calibrate menu and the submenu sk1: Tare Meas .
□
Select operating mode for tare measurement: Time or
Length .
□
Time: enter measuring time in seconds and confirm with
< enter > (see also section 7.1).
□
Length: enter the belt length in meters and confirm with
< enter > (see also section 7.1).
□
Empty conveyor system and make sure that it remains
empty over the entire measuring time.
□
Push the < run > button. The tare measurement starts
and the tare count rate is displayed.
□
At the end of the measurement, the averaged tare count
rate and the selected belt length or time is displayed.
□
Store the measured value with < enter >.
For more information see Tare Measurement page 68.