VEGA VEGADIF 65 4 … 20 mA_HART - Manual (Page 80)

80
11 Supplement
VEGADIF 65 • 4 … 20 mA/HART
36128-EN-130417
Ʋ Turn down > 15 : 1 ±(0.0015 % x TD + 0.053 %) of the set span + influence
of the chemical seal
Influence of the product or ambient temperature
Applies to instruments in basic version with digital signal output (HART, Profibus PA, Foundation
Fieldbus) as well as to instruments with analogue current output 4 … 20 mA. Specifications refer
to the set span. Turn down (TD) = nominal measuring range/set span.
Temperature range Measuring range Thermal changes of the zero sig-
nal and the output span relating
to the adjusted span
-10 … +60 °C (+14 … +140 °F) 10 mbar, 30 mbar ±(0.31 x TD + 0.06) %
100 mbar ±(0.18 x TD + 0.02) %
500 mbar, 3 bar ±(0.08 x TD + 0.05) %
16 bar ±(0.1 x TD + 0.1) %
16 bar ±(0.08 x TD + 0.05) %
-40 … +10 °C (-40 … +50 °F)
+60 … +85 °C (+140 … +185 °F) 10 mbar, 30 mbar ±(0.45 x TD + 0.1) %
100 mbar ±(0.3 x TD + 0.15) %
500 mbar, 3 bar ±(0.12 x TD + 0.1) %
16 bar ±(0.15 x TD + 0.2) %
40 bar ±(0.37 x TD + 0.1) %
Applies also to instruments with analogue 4 … 20 mA current output and refers to the set span.
Thermal change, current output
< 0.05 %/10 K, max. < 0.15 %, each with -40 … +80 °C
(-40 … +176 °F)
0,15 %
-0,15 %
-40°C -20°C
20°C
40°C 60°C 80°C
Fig. 60: Thermal change, current output
Influence of the system pressure on the zero point and span
316L, Alloy C276-, Alloy C276 gold-rhodium coated diaphragm
Measuring cell 10 mbar 30 mbar 100 mbar 500 mbar
Influence of the sys-
tem pressure to the
zero point
±0.15 % of
URL/7 bar
±0.35 % of
URL/70 bar
±0.15 % of
URL/70 bar
±0.075 % of
URL/70 bar
Influence of the sys-
tem pressure to the
span
±0.035 % of
URL/7 bar
±0.14 % of
URL/70 bar
±0.14 % of
URL/70 bar
±0.14 % of
URL/70 bar