KROHNE BM 102 Handbook - Manual (Page 37)

BM 102 37
How to configure the gauge to give volume readings
User menu PCSTAR 2 function 1.7.2 (HART
® submenu 2.1.7)
• To be able to measure the volume, a conversion table (strapping table) will need to be created
using the PCSTAR 2 program or the HART® communicator.
• The strapping table assigns defined volumes to the various levels.
• In the case of non-symmetrical tanks, e.g. tanks with dished bottom, the accuracy of
volumetric measurement will depend on the number of entered “level/volume pairs”. The
maximum number of pairs (points) that can be set is 20. The volume is linearly determined
(interpolated) between 2 points.
• The conversion table is generally used for volume, but can also be used for mass and flow.
Five points have been set in the following example.
Procedure 3: creating a strap table the probe by assigning a volume to a user-defined level
(using PCSTAR 2)
Step
Action Data entered/value selected
1 Connect to the gauge as described in section 3.3.1. n/a
2 Press function key F2 or left click on F2-connection at
the bottom of the window. This will open the user
configuration menu. n/a
3 Go to user function 1.1.1: Tank height to enter value
(click on field and type in value) 6.00 m or 19.69 ft*
4 Go to user function 1.1.2: Dead zone to enter blocking
distance value. 0.40 m or 1.31 ft*
5 Go to user function 1.1.6: Probe length to enter value 5.80 m or 19.03 ft*
6 Go to user function 1.2.4: Length Unit to select length
units. m or ft
7 Go to user function 1.2.5: Volume unit to select volume
units m³ or ft³
8 Go to user function 1.7.2: Input table. A maximum of 20
points can be entered. For each point a level and a
volume must be entered. Each point should have a
value higher than preceding one. See table below
Input table
Point Level
Volume
1 0.0 m or 0.0 ft 0.0 m³ or 0.0 ft³
2 0.20 m or 0.66ft 0.5 m³ or 17.66 ft³
3 0.75 m or 2.46ft 1.0 m³ or 35.31 ft³
4 1.00 m or 3.28ft 1.5 m³ or 52.97 ft³
5 5.60 m or 18.37ft 16.8 m³ or 593.3 ft³
*Max. level = tank height – dead zone
= 6.00 m – 0.40 m or 19.69 ft – 1.31 ft
= 5.60 m or 18.37 ft, equivalent to a volume of 16.80 m³ or 593.3 ft³
Note:
The level can effectively be measured between 0.20 m or 8” and 5.60 m or 18½ ft. When the
product level drops below the tip of the probe, the BM 102 will indicate that there is still remains of
0.20 m or 8”. Accordingly, the BM 102 can only indicate a level between 0.20 m or 8” and 5.60 m
or 18½ ft, since it only measures along the probes. The size of the dead zone depends on the
installation and on the probe type.