Instruction Manual

Instruction Manual
D103434X012
Blocks
November 2014
144
Compensation - Linear. This allows a ratio to be set up that increases the level indication at block output for an increase
in the tank temperature relative to ambient temperature.
This application can be applied to very large storage tanks whose contents are subject to thermal expansion and
contraction during seasonal changes in temperature.
Figure B‐20. Arithmetic Function Block Diagram Example
Advanced Topics
The parameter, ARITH_TYPE, determines how PV and the compensation terms (t) are combined. You may select from
nine (9) commonly used math functions, shown below. COMP_HI and COMP_LO are compensation limits.
If there is a divide by zero and the numerator is positive, f is set to COMP_HI; if the numerator is negative, then f is set
to COMP_LO. The square root of a negative value will equal the negative of the square root of the absolute value.
Imaginary roots are not supported.
If there is a divide by zero and numerator is positive, f will be limited to COMP_HI; if the numerator is negative, f will be
limited to COMP_LO.
Compensation inputs which are not usable are not included in the calculation. PV is always included.