Configuring Linearization; Defining Linearization; Configuring Device Linearization - ABB LLT100 Operating Instructions Manual
Laser level transmitter oi-llt100-en rev. d
Hide thumbs
Also See for LLT100:
- Operating instruction (4 pages) ,
- Functional safety manual (32 pages)
Table of Contents
8 Configuring linearization
8.1 Defining linearization
In the LLT100, the linearization function allows more accurate
volume measurements by referring to a preset linearization
table. It is especially useful in irregularly shaped vessels
(cylindrical lying tanks, spherical gas tanks, etc.), but in all
applications, regardless of vessel shape, it is used to convert
level to volume.
The linearization table provides the instrument with data
regarding known volumes at specific levels in the irregularly
shaped part of a vessel.
Below is an example of the relationship between a linearization
table actual measured levels:
Point 3
Point 2
Point 1
Point 0
Figure 19 Actual level vs. linearization table points
If Figure 19 was translated in actual values, it could be put in
a table as such:
Table 3: Level vs. Volume in linearization feature
Linearization
Level (m)
point
0
0
1
10
2
15
3
50
As you can see, the level-to-volume conversion does not
progress in a linear fashion because of the irregular shape of
the vessel. By creating a linearization table with proper values,
this function allows to compensate for the irregular shape of
the vessel.
8.2 Configuring device linearization
The linearization function, available only in Advanced mode, is
always used to convert level to volume in all applications. In
tanks with an irregular shape, you can enter between 2 and
21 linearization points.
The first point is always the point with the lowest value and all
other points must be set in increasing order.
To properly configure the linearization feature:
1. In the Easy Setup menu, configure the instrument for
volume measurements, as explained in section 5.2.2,
"Setting volume parameters", on page 16.
This step takes care of the complete linearization setup.
Once the setup is configured, you have to set the points in
50 m
the linearization table.
2. In the Device Setup menu, select Linearization > Points.
3. Select a linearization point with the Up and Down arrow
keys.
4. Press the Left arrow key to select the measured level (In).
15 m
10 m
0 m
5. Press the Right arrow key to edit the In value, and press OK
when you are done.
6. Press the Left arrow key to select the volume associated
with the measured level (Out).
Associated
volume (ft
)
3
0
100
300
1500
7. Press the Right arrow key to edit the Out value, and press
OK when you are done.
8. Press the Left arrow key to move to the next linearization
point, and repeat steps 4 to 8 for all the required linearization
points.
OI-LLT100-EN Rev. D | User Guide 25
- Quick Links:
- Electrical
- Connecting the Instrument
Hide quick links:
Table of Contents
