KROHNE BM 102 Handbook - Manual (Page 63)

BM 102 63
5 Technical data
5.1 Technical data
Application
Range of applications Continuous level measurement of liquids, pastes, slurries and
powders
Function and system design
Measuring principle
Time domain reflectometry
Equipment architecture See section 5.2
Input
Measured variable Distance (between the reference point – gauge flange facing –
and the product surface), level, liquid interface & volume
Measurement range Variable according to probe type, see Equipment architecture,
section 5.2.1
Blocking Distance
(dead zone) Variable according to probe type, see probe measurement limits,
see section 5.2.2
Output
Analogue 4 … 20 mA, passive output
Load
Passive outputs 750 ohms maximum
Error signal 22 mA
Temperature drift 25 ppm / K
Resolution ± 3 µA
Digital HART®, passive output
Digital, Ex ia HART®, passive intrinsically-safe output
Signal on alarm Status markers via PC STAR 2 or HART® controller (HHC)
Performance characteristics
Accuracy
Level measurement Liquids when probe length, L ≤ 15 m or 50 ft.
± 15 mm or 0.6 “ outside the dead zone
Optional: ± 5 mm or 0.2 “
Liquids when probe length, L > 15 m or 50 ft.
± 0.1% of the measured distance
Optional: ± 0.05% of the measured distance
Solids (powders)
± 20 mm or 0.8 “
with 4 … 20 mA current output
± 0.01% of the measured distance
Reference operating conditions
Ambient temperature
+20°C ± 5°C or +68°F ± 9°F
Ambient air pressure 1013 mbar abs. ± 20 mbar or 14.69 psig ± 0.29 psi
Relative air humidity 60% ± 15%
Reference target - coaxial probe : water surface
- single probe : Ø 0.8 m or Ø 31.5 in. metal plate
- twin probe : metal block “short circuit”
Free space diameter > 300 mm * or 11.81” *
Distance to obstruction > 1 m or > 3.28 ft.
* not necessary for coaxial probe.