Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 196

■Inverse engineering value conversion
This function block converts the setting value (SV) of an engineering value into a setting value (SV) in percentage (%).
100
SV(%)= ×(SV-RL)
RH-RL
RH: Engineering value high limit, RL: Engineering value low limit, SV: Setting value
■Tracking processing
The following table shows whether tracking processing to the input variable CASIN_T is performed or not.
Condition
Tracking Flag (TRK)
1
0
■Disable alarm detection
This function block sets whether to detect alarms (ALM) or not in the deviation check.
Item
Disable alarm detection by setting tag data
Disable alarm detection by loop stop processing
■Auto tuning (AT1)
This function block detects dynamic characteristics and automatically calculates a proportional gain (Kp), integral time (Ti),
and derivative time (Td) for PID operations. ( Page 594 Auto tuning)
• Auto tuning is for setting initial values of the proportional gain (Kp), integral time (Ti), and derivative time (TD) for PID
operations. The ZN method: Ziegler-Nichols' step response method is used for calculating the values.
• Auto tuning can be performed only in the MANUAL mode.
■Loop stop processing
When the stop alarm (SPA) of the alarm (ALM) is TRUE, this function block performs the following processing.
• MV is cleared to 0.
• The control mode is automatically switched to MANUAL.
• When DVLA of the alarm (ALM) has occurred, the DVLA is reset.
• No alarm is detected in the deviation check.
■Processing operation
: Performed, : Not performed
Control mode Processing operation
Deviation
check

MAN, CMV, AUT

CAS, CSV
*1 Tracking is performed when the tracking flag (TRK) is 1.
*2 An alarm whose corresponding bit is TRUE (Valid) in the disable alarm detection (INH) is not detected.
*3 Auto tuning can be performed only in the MANUAL mode.
10 LOOP CONTROL OPERATION
194
10.3 Velocity Type PID Control (Enable Tracking for primary loop) (M+P_PID_T)
Setting Value (SV) Used (SVPTN_B0)
FALSE
TRUE
FALSE or TRUE
PID operation Engineering
value
conversion
 
 
Result
The input variable CASIN_T is tracked.
The input variable CASIN_T is not tracked.
Disable alarm detection processing
If the following bits in the disable alarm detection (INH) are TRUE, no DVLA of
the alarm (ALM) will be detected.
• ERRI
• DVLI
Page 194 Loop stop processing
Inverse Tracking
engineering
value
conversion
*1
 
 
Alarm Auto tuning
*2 *3
 
*2
 