IDEC MICROSmart FC6A Series Ladder Programming Manual page 419

Process Variable (PV) (S1+0, S1+1) is the value of the input value of the specified analog input converted to the full scale in
the range of PV Lower Range Value (S1+22, S1+23) to PV Upper Range Value (S1+24, S1+25).
Analog Input
Notes:
• When Analog Input is specified, the analog I/O cartridge and analog I/O module must be configured in the Module Configuration Editor.
For details on how to configure analog inputs, see Chapter 9 "Analog I/O Modules" in the "FC6A Series MICROSmart User's Manual".
• The analog volume on the CPU module cannot be specified as an analog input.
When Data Register is specified
The PIDD instruction loads the value (data type F (float)) stored in the two data registers starting from the specified data
register as the process variable.
If the data register value is higher than PV Upper Range Value, the process variable will be PV Upper Range Value. If the
data register value is lower than PV Lower Range Value, the process variable will be PV Lower Range Value. The process
variable is stored in Process Variable (PV) (S1+0, S1+1).
Data Register
(Float Value)
2. PV Upper Range Value (URV) (S1+24, S1+25), PV Lower Range Value (LRV) (S1+22, S1+23)
Sets the full scale of Process Variable (PV) (S1+0, S1+1) with the minimum and maximum values.
If the process variable is higher than PV Upper Range Value (S1+24, S1+25), Process Variable (PV) (S1+0, S1+1) will be PV
Upper Range Value. If the process variable is lower than PV Lower Range Value (S1+22, S1+23), Process Variable (PV) (S1+0,
S1+1) will be PV Lower Range Value. Error code 109 will be stored in Error Status (S1+34, S1+35) in those cases.
PV Upper Range Value (S1+24, S1+25) and PV Lower Range Value (S1+22, S1+23) are set as data type F (float) between
-32,768.0 to 65,535.0.
3. Control Mode and Set Point (S3+1 to S3+3)
Specifies the PID control mode and the referenced set point.
Select Auto Mode - LSP (S1+2, S1+3) or Cascade Control - RSP (S1+4, S1+5).
When Auto Mode - LSP (S1+2, S1+3) is selected
The PIDD instruction becomes Auto Mode. Auto Mode Select (S3+2) will be on, Manual Mode Select (S3+1) will be off, and
Cascade Control Mode Select (S3+3) will be off.
Store the set point in Set Point (SP) (S1+2, S1+3) in the range of SP Low Limit and SP High Limit.
If the value of Set Point (SP) (S1+2, S1+3) is higher than SP High Limit, the PID control set point will be SP High Limit. If the
value of Set Point (SP) (S1+2, S1+3) is lower than SP Low Limit, the PID control set point will be SP Low Limit. If the set point
is outside the range of the high limit and low limit, error code 106 will be stored in Error Status (S1+34, S1+35).
PV Upper Range Value (S1+24, S1+25)
Full Scale of
Process Process Variable (PV) (S1+0, S1+1)
Variable (PV)
PV Lower Range Value (S1+22, S1+23)
PV Upper Range Value (S1+24, S1+25)
Full Scale of
Process Process Variable (PV) (S1+0, S1+1)
Variable (PV)
PV Lower Range Value (S1+22, S1+23)
FC6A S MICROS L
ERIES MART
P M
ADDER ROGRAMMING ANUAL
19: PID C
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FC9Y-B1726
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NSTRUCTION
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