VEGA VEGABAR 74 4 … 20 mA_HART User Manual
Page 30
D
eviation with absolute pressure measuring range 0.1 bar
-
T
urn down 1:1 up to 5:1
<
0.25 %
x TD
-
T
urn down up to 10:1
<
0.05 %
x TD
Influence of the product or ambient temperature
A
pplies to digital HART interface as well as to analogue current output 4 … 20 mA.
S
pecifications refer to the set span. Turn down (TD) = nominal measuring range/set span.
Average temperature coefficient of the zero signal
I
n the compensated temperature range of 0 … +100 °C (+212 °F), reference temperature
20 °C (68 °F):
A
verage temperature coefficient of the zero signal
-
T
urn down 1:1
<
0.05 %/10 K
-
T
urn down 1:1 up to 5:1
<
0.1 %/10 K
-
T
urn down up to 10:1
<
0.15 %/10 K
O
utside the compensated temperature range:
A
verage temperature coefficient of the zero signal
-
T
urn down 1:1
typ. <0.05 %/10 K
Thermal change of the current output
A
pplies also to the analogue 4 … 20 mA current output and refers to the set span.
T
hermal change, current output
<
0.15 %
at -40 … +80 °C (-40 … +176 °F)
Long-term stability (similar to DIN 16086, DINV 19259-1 and IEC 60770-1)
A
pplies to digital HART interface as well as to analogue current output 4 … 20 mA.
S
pecifications refer to the set span. Turn down (TD) = nominal measuring range/set span.
L
ong-term drift of the zero signal
<(0.1 %
x TD)/1 year
Total deviation (similar to DIN 16086)
T
he total deviation (max. practical deviation) is the sum of basic accuracy and long-term
stability:
F
total
= F
perf
+ F
stab
F
perf
= √((F
T
)
2
+ (F
K
l
)
2
)
W
ith
-
F
total
: T
otal deviation
-
F
perf
: B
asic accuracy
-
F
stab
: L
ong-term drift
S
upplement
30
VEGABAR
74 - 4 … 20
mA/HART
28432
-EN
-070718