Standard Input/Output Processing - Toshiba V Series User Manual

Chapter 3 Software Functions
3.4.3

Standard input/output processing

I/O data of I/O module can be corrected, converted or alarm processing can be executing by
setting necessary parameters to tag variables. For details of tags, see E.3 "Tag Variables (PV,
LP, PB)."
(1) PV processing
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The following operations will be executed according to the indicator variable (parameter)
setting.
• Analog instantaneous value conversion
Normalization, temperature/pressure correction, filtering and engineering unit
conversion will be executed in the following order.
<1> Normalization
Normalization will be executed according to the high range (CH) and low range
(CL) of the input counter.
When input counter is CH, PV becomes RH (instrument range high limit)
When input counter is CL, PV becomes RL (instrument range low limit)
<2> Temperature/pressure correction
The following are executed in the order listed below.
<2-1> Temperature/pressure correction
<2-2> Square root extraction
<2-3> Low cutoff
<3> Filtering
Output value this time =
[Input value this time × (1-FT)] + [Previous output value × FT]
<4> Engineering unit conversion
<5> Correction by application program
PV value will be corrected by application program according to the setting of
PV/PVC direct specification (DIC).
If DIC setting is PV = PVC, the result of the standard input processing will be stored
to PV and PVC.
If DIC setting is PV<>PVC, the result of the standard processing will be stored to
PVC and the value corrected by the application program will be stored to PV.
• Pulse instantaneous value conversion
Input from an intelligent serial PI module only is handled.
The following instantaneous value calculation will be executed.
(Instantaneous value) = (Pulse count difference) × PU × D × K × T / (Scan time)
In the same way as analog instantaneous value, the value can be corrected by
application program.
• Analog integrated value conversion
The following integrated value calculation will be executed.
(Integrated value this time) =
[(Instantaneous value this time) × D × K × (Scan time) / T] + (Previous integrated time)
While the integrated value is being reset, its value is kept to zero
If the value exceeds the maximum integrated value (MAX), overflow processing
[(Integrated value−MAX)] will be executed.
• Pulse integrated value conversion
Input (0−65535 endless counter) from an intelligent serial PI module only is handled.
The following integrated value calculation will be executed.
(Integrated value this time) =
[(Pulse count difference) × PU × D × K] + (Previous integrated time)
While the integrated value is being reset, its value is kept to zero
Model 1000 Loop Controller L1 LC511, 512 User's Manual