Endress+Hauser Micropilot M FMR231, Operating Instructions Manual

Page: 90 / 114

Technical data Micropilot M FMR231 with FOUNDATION Fieldbus
90 Hauser
Maximum measured error Typical statements for reference conditions, include linearity, repeatability, and hysteresis:
• FMR 231: up to10 m ±10 mm, off10 m ±0.1% of measuring range
Resolution Digital
• FMR 231: 1mm / 0.03 % of measuring range
Reaction time The reaction time depends on the parameter settings (min. 1 s). In case of fast level changes, the
instrument needs the reaction time to indicate the new value.
Influence of ambiente
temperature The measurements are carried out in accordance with EN 61298-3:
• digital output (HART, PROFIBUS PA, Foundation Fieldbus):
– FMR 231
average T
K
: 5 mm/10 K, max. 15 mm over the entire temperature range -40 °C...+80 °C
Effect of gas phase High pressures reduce the propagation velocity of the measuring signals in the gas/vapor above the
fluid. This effect depends on the gas/vapor and is particularly large for low temperatures. This
results in a measuring error that gets bigger as the distance increases between the device zero point
(flange) and product surface. The following table illustrates this measured error for a few typical
gases/vapors (with regard to the distance; a positive value means that too large a distance is being
measured):
Note!
When the pressure is known and constant, this measured error can, for example, be compensated
by means of linearization.
Gas phase Temperature Pressure
°C °F 1 bar/14.5 psi 10 bar/145 psi 50 bar/725 psi 100 bar/1450 psi 160 bar/2320 psi
Air
Nitrogen 20 68 0.00 % 0.22 % 1.2 % 2.4 % 3.89 %
200 392 -0.01 % 0.13 % 0.74 % 1.5 % 2.42 %
400 752 -0.02 % 0.08 % 0.52 % 1.1 % 1.70 %
Hydrogen 20 68 -0.01 % 0.10 % 0.61 % 1.2 % 2.00 %
200 392 -0.02 % 0.05 % 0.37 % 0.76 % 1.23 %
400 752 -0.02 % 0.03 % 0.25 % 0.53 % 0.86 %
Gas phase Temperature Pressure
°C °F 1 bar/14.5 psi 10 bar/145 psi 50 bar/725 psi 100 bar/1450 psi 160 bar/2320 psi
Water
(saturated
steam) 100 212 0.20 % — — — —
180 356 — 2.1 % — — —
263 505.4 — — 8.6 % — —
310 590 — — — 22 % —
364 687.2 — — — — 41.8 %