Auxiliary Transducer Block - Honeywell SLG 700 Option Manual

3.6

Auxiliary Transducer Block

Auxiliary Transducer block provides advanced configuration support of Linearization, Volume and
Correlation Algorithm. It also provides support to view the Echo curve.
3.6.1. Linearization
When the Linearization option is enabled, the transmitter's measured values are replaced by
corresponding user-specified corrected values from the linearization table. The Linearization Table
consists of Measured_Level1 Table, Measured_Level2 Table, Corrected_Level1 Table and
Corrected_Level2 Table. See Table 9 for more detail.
Before enabling Linearization option linearization table must be configured. Tables can be configured
either in dry or wet.
Wet Linearization:
When the measured level for the tank reaches a level where the corresponding corrected level is
known then we can use Wet linearization. If Linearization Type is Wet, then it is allowed to
enter/correct single entry in the Linearization table at a time using method. While executing Level Wet
Linearization Method, Measured Level is cannot be edited by user. Value of Product Level or value of
Interface Level (Measured Product Type is Two Liquid Flooded) is copied in the Measured Level
table based on the selected Linearization Table Index. Linearization table entry is limited by value of
Linearization table Size. If entry exceeds linearization size, the Parameter Check Error is triggered.
Dry Linearisation:
The user can do manual entry in pairs of Measured Level and a corresponding Corrected Level in
Linearisation Table to enable Dry Linearisation.
Please refer Table 8: Auxiliary Transducer block parameters for more details on Linearization.
Note: The Level Linearization feature does not affect the values reported for the Distance to Product
and Distance to Interface device variables. If Level Linearization is enabled, the distance and
associated level are no longer described solely by the basic geometry and it is possible that the Product
Level will not be equal to (Sensor Height – Level Offset – Distance to Product). Likewise for the
Interface if is being calculated.
3.6.2. Description of correlation algorithm
Each object in the tank (reference, surface, end of probe, interface (for two liquids), process connector
(for remote mount) reflects an echo wave with its own signature or model shape.
Each model's shape is described with parameters such as width, gain (amplitude), and attenuation.
These models are configured at the factory according to the customer's specified configuration. The
correlation algorithm searches each part of the captured echo curve looking for the model echo from
each object and, if found, reports the distances in the DTM.
The models will work as configured in the factory, assuming the customer's ordered configuration is
correct. If for some reason the surface or other objects are not being detected correctly try the
following steps. Often these steps will fix the problem.
Check the basic configuration settings and adjust if necessary.
1.
Check advanced configuration settings, especially probe settings and adjust if necessary.
2.
Read Echo curve using FDM/DTM for troubleshooting. Based on the Echo signal,
3.
required correlation algorithm configuration changes should be adjusted if there is a
measurement problem. Refer to section 6.8.7 Echo Curve.
Rev.5 FOUNDATION Fieldbus Option User's Manual Page 35