Mitsubishi Electric MELSEC iQ-R Series - Page 1348

1346
11 PROCESS CONTROL INSTRUCTIONS
11.3 Control Operation Instructions
Processing details
This instruction gradually brings the output value (BW) closer to the output set value (E1) from the output control value (E2)
when the control mode changes from manual to automatic.
When the output value (BW) enters the range specified by the lag band (a) on the basis of the output set value (E1), the
instruction brings it closer to the output set value (E1) with a primary lag.
In manual mode (mode switching signal (e1) = 0), the instruction calculates the output value (BW), initial deviation value (Xq),
and deviation (Xp) from the following expressions.
• Output value (BW) = output control value (E2)
• Initial deviation value (Xq) = output control value (E2) - output set value (E1)
• Deviation (Xp) = output control value (E2) - output set value (E1)
In automatic mode (mode switching signal (e1) = 1), the instruction calculates the output value (BW) from the following
expressions.
However, in automatic mode in which lag time (T)execution cycle (T), output value (BW) = output set value (E1), deviation
(Xp) = Xp'.
Operation error
Condition |Xp|>a |Xp|a
Xp
BW BW=E1+Xp
On the condition above,
•BW=E1
•Xp=Xp'
BW=E1+Xp
provided that |Xp|10
-4
•BW=E1
•Xp=Xp'
Error code Error content
3400H An invalid operation (such as division by zero) is performed.
3402H The value specified by (s1), (s2), or (d2) is a subnormal number or NaN (not a number).
3403H An overflow has occurred.
Xp=Xp'-
Xq
T
© T
T
Xp= Xp'
T+©T
|Xp|<=
T
|Xq|
©T