SEFRAM 902406500, Руководство пользователя

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Page 12.4
12.2. Accuracy class
– class index
This is one of the most important concepts of the CEI recommendation; it tends to shorten
the list of specifications. To do so, it introduces the concept of PREDICTIVE CLASS that
depends on the C CLASS INDEX.
The normalized values of the class index are: C = 0.1, 0.25, 0.5 and 1.
The intrinsic error (in the reference conditions) does not C % (the manufacturer
may also specify this limit of the intrinsic error as an absolute value (ex. + 5 µV) for the first
calibers).
The variations (of the measured value) with the variations of one of the influential variables
in the nominal range of use do not exceed:
-
C % for the position for the magnetic induction with external source and parasite
tensions
- 0.5 C% for the power supply source
- 0.3 C% according to the class index at ambient temperature (0.15% for the 0.25 class).
In addition, the insensitivity range should not exceed:
-
C% in the reference conditions
- 1,5C% for the maximal resistance of the external measurement circuit
- 2C% for parasite tensions
And the excess should not be more than 2C% (4C% within the limits of the power supply
source).