Ambient Conditions - Siemens SITRANS LG250 Operating Instructions Manual

Temperature drift - Digital output
Additional deviation through electromag-
netic interference acc. to EN 61326
Specifications apply also to the current output
Temperature drift - Current output
Deviation on the current output through
analogue/digital conversion
Additional deviation through electromag-
netic interference acc. to EN 61326
Influence of the superimposed gas and pressure to the accuracy
The propagation speed of the radar impulses in gas or vapour above the medium is reduced by
high pressure. This effect depends on the superimposed gas or vapour and is especially large at
low temperatures.
The following table shows the resulting deviation for some typical gases and vapours. The specified
values refer to the distance. Positive values mean that the measured distance is too large, negative
values that the measured distance is too small.
Gas phase
Air
Hydrogen
Steam (saturated
steam)
Characteristics and performance data
Measuring cycle time
Step response time
8)
Max. filling/emptying speed

Ambient conditions

Ambient, storage and transport tempera-
ture
Also for the additional current output (optional)
7)
Time span after a sudden measuring distance change by max. 0.5 m in liquid applications, max 2 m with bulk
8)
solids applications, until the output signal has taken for the first time 90 % of the final value (IEC 61298-2).
80
Temperature
1 bar (14.5 psig)
20 °C (68 °F) 0 %
200 °C (392 °F) -0.01 %
400 °C (752 °F) -0.02 %
20 °C (68 °F) -0.01 %
200 °C (392 °F) -0.02 %
400 °C (752 °F) -0.02 %
100 °C (212 °F) 0.26 %
180 °C (356 °F) 0.17 %
264 °C (507 °F) 0.12 %
366 °C (691 °F) 0.07 %
SITRANS LG250 - Operating Instructions
±3 mm/10 K relating to the max. measuring range or
max. 10 mm (0.394 in)
< ±10 mm (< ±0.394 in)
7)
±0.03 %/10 K relating to the 16 mA span max. ±0.3 %
< ±15 µA
< ±150 µA
10 bar (145 psig)
0.22 %
0.13 %
0.08 %
0.1 %
0.05 %
0.03 %
-
2.1 %
1.44 %
1.01 %
< 500 ms
≤ 3 s
1 m/min
-40 ... +80 °C (-40 ... +176 °F)
Pressure
50 bar (725 psig)
1.2 %
0.74 %
0.52 %
0.61 %
0.37 %
0.25 %
-
-
9.2 %
5.7 %
PBD-51041388