<Appendix 3. Arithmetic (Ar) Block>
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IM 01E21A02-03EN
A3.4.2 Status Handling
The setting of INPUT_OPTS is applied to the input status. When INPUT_OPTS is applied, there
are cases where the PV status becomes “good” even if the status of main inputs is “uncertain”, or
the status of auxiliary inputs is “uncertain” or “bad”.
The PV status is classified by the following:
• If the statuses of two main inputs are both “good”,
Or if both statuses of two main inputs are other than “good”
See A3.2.1 Main Inputs.
• If only one of the statuses of two main inputs is “good”
- If the status of IN is “good” and the status of “IN_LO” is anything other than “good”
IN > RANGE_LO => The status of IN applies.
IN ≤ RANGE_LO => See A3.2.1 Main Inputs.
- If the status of IN is anything other than “good” and the status of “IN_LO” is “good”
IN_LO < RANGE_HI => The status of IN_LO applies
IN_LO ≥ RANGE_HI => See A3.2.1 Main Inputs.
The exception is that if RANGE_LO > RANGE_HI, the PV status is made “Bad.
ConfigurationError”.
The input status irrelevant to the computing equation selected by ARITH_TYPE will be ignored
and does not affect other statuses. The statuses of outputs (OUT.Status and PRE_OUT.Status)
are interpreted as the status of the worst input among the statuses of PV and auxiliary inputs
(IN_1, IN_2, and IN_3) to which INPUT_OPTS has been applied.
Example)
Case 1
Case 2
Case 3
PV
Good
IN_1
Uncertain
IN_2
Bad
IN_3
Bad
INPUT_OPTS
IN_1
Handled as a “good”
input if its status is
“uncertain”.
No option
IN_2
Handled as a “good” input if its status is “bad”.
No option
IN_3
No option
ARITH_TYPE
1) Flow rate compensation (linear) in A3.3.1, “Computing Equations”
OUT.Status
Good
Uncertain
Bad
