BLN nobel G5, Техническое руководство

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G5 Weighing Instrument
9-1
9. Adaptation for legal weighing
General
WELMEC, an European co-operation of legal metrology authorities, has made a series
of publications to implement the use of the harmonised standards of legal weighing.
The WELMEC 2 document has a section, ‘Compatibility of Modules Data sheet’ to
investigate if the electronic indicator, load cells and connecting elements can be used
together as a weighing instrument, based on the part certificates of the single
components. Four tables with data for the weighing instrument (total scale), electronic
indicator, load cell and connecting elements are used to test 10 conditions which must
be fulfilled for approval. For explanations of terminology in this paper see the WELMEC
2 document and the G5 Weighing Instrument Technical Manual. The WELMEC
documents can be found on internet ”
http://www.welmec.org/latest/guides/ ”. Select
WELMEC guide 2, and then chapter 10 Compatibility of modules.
Non-Automatic Weighing Instrument
EN45501, OIML 76-1, WELMEC 2, chapter 10, Compatibility of
modules
Table for Weighing instrument
The general data of the total scale is entered in this part.
•
accuracy class class
This can be III or IV.
•
maximum capacity Max
Maximum capacity of the scale.
•
verification scale interval e
The indication stepping size.
•
number of verification scale intervals n
The number of indicator steps from 0 to Max,
Max/e.
•
reduction ratio R
The fraction of the weight coming
to the load cells via a reduction beam.
This number is 1 at direct loading of the load cells.
•
number of load cells N
•
correction factor Q
Set to 1.
•
dead load of load receptor DL
Think of it as the weight that has to be removed
from the scale to get the load on the load cells to
zero when the scale is empty. Can be set to 0 if
the load cell has no low load restriction.(E
min
=0)
•
lower limit of temperature range T
min
Range -10
°
C to (T
max
-30)
°
C.