LSIS XGK-CPUU - Common Bit Area

Chapter 10 Built-in PID Functions
10 - 11
10.5.1 Common bit area
The common bit area is the part that contain all bit data for the 32 loops. All information 32 loops have for a
signel item is combined to take the form of 32 bit double word; the nth bit provides information on the nth loop;
m is the hexadecimal value of loop number n.
(1) _PIDn_MAN (PID MANual operation enable) - Setting Area
K Device Area : K10000+m
Unit : Bit
This allows you to determine whether the PID function of the nth loop will operate in AUTO or in Manual.
In AUTO, the result of performing a normal PID operation is output; In MANUAL, a random Set Value
desired by the user (_PIDn_MV_man) is output without performing the PID operation.
If the corresponding bit is Off, then it is set to [Default] AUTO.
(2) _PIDn_PAUSE (PID PAUSE mode) - Setting Area
K DEVICE AREA : K10020+m
Unit : Bit
This allows the nth PID Loop to enter into PAUSE
Even when switching from PAUSE to RUN again, the control continues to operate. If the system state is
changed in PAUSE, the control system may produce an unexpected result. So, be very careful when using
the the PAUSE function.
If the corresponding bit is Off, [Default] PAUSE is cleared.
(3) _PIDn_REV (PID REVerse operation) - Setting Area
K DEVICE AREA : K10040+m
Unit : Bit
This allows you to set the control system as Forward system or Reverse system.
If the system state rises as the system input value rises, it is defined as Forward system; If the system
states falls as the system input value rises, it is Reverse system.
A boiler is a Forward system because the temperature rises as the system input rises; a cooler is a
Reverse system because the temperature falls as the system input rises.
If the corresponding bit is Off, it is set to [Default] Forward system.
Note
_PIDn_PAUSE
(1) Putting the PID loop into PAUSE by using PIDn_PAUSE and PIDPAUSE brings all
operations to a stop and outputs the last calculation values before PAUSE. If the system
state is changed but proper control is not exercised, the control system may produce an
unexpected result. So, be very careful when using the the PAUSE function.
(2) In the first PLC scan, PIDRUN performs initialization to turn the PAUSE bit to Off. If PLC is
turned on in PAUSE, it quits the PAUSE mode and enters into the STOP or Run mode.