56
9 Supplement
WIKA Operating Instructions - Process pressure transmitter IPT-2x
The deviation corresponds to the value F
Kl
in chapter "
Calculation of the total deviation
". The value
results out of the accuracy class and the respective turn down.
Accuracy class
13)
Non-linearity, hysteresis and repeata-
bility with TD 1 : 1 up to 5 : 1
Non-linearity, hysteresis and repeata-
bility with 5 : 1
0.075 %
< 0.075 %
< 0.015 % x TD
0.1 %
< 0.1 %
< 0.02 % x TD
0.2 %
< 0.2 %
< 0.04 % x TD
Influence of the medium or ambient temperature
Thermal change zero signal and output span through product temperature
Applies to the
digital
signal output (HART, Profibus PA, Foundation Fieldbus) as well as to the
ana-
logue
current output 4 … 20 mA and refers to the set span. Turn down (TD) is the ratio "nominal
measuring range/set span".
The thermal change of the zero signal and output span corresponds to the value F
T
in chapter
"
Calculation of the total deviation (according to DIN 16086)
".
Piezoresistive/strain gauge measuring cell
(TD 1:1)
T / °C
50 °C
10 °C 20 °C
40 °C
70 °C
-40 °C
100 °C
150 °C
0,15
-0,15
-0,3
-0,45
-0,6
-0,75
-0,9
0,3
0,45
0,6
0,75
0,9
F/
%
TBasis
Fig. 27: Basic temperature error F
TBasis
at TD 1 : 1
The basic temperature error in % from the above graphic can increase due to the additional factors
such as accuracy class (factor FMZ) and Turn Down (factor FTD). The additional factors are listed
in the following tables.
Additional factor through accuracy class
Accuracy class
0.075 %, 0.1 %
0.2 %
Factor FMZ
1
3
Additional factor through Turn Down
13)
Different availability depending on measuring range and process fitting
