Adjustment Of Control Gain; Proportional Gain And Integral Time; Additional Gain And Dead Band Width - Mitsubishi LE-30CTN Instruction Manual

5. Automatic Operation and Functions
5.5

Adjustment of control gain

• If the tension is not stabilized during automatic control, adjust the proportional gain or the integral time.
• When starting the machine, or after changing the set tension value, if it takes a long time to obtain the target
tension, adjust the additional gain or dead band width.
5.5.1

Proportional gain and integral time

• If the tension is not stabilized during automatic control, adjust the proportional gain or the integral time.
[1] Proportional gain
[2] Integral time
• Gradually change the integral time and the proportional gain in turns.
• Setting screen
5.5.2

Additional gain and dead band width

• The dead zone gain and dead band width are not required to be changed in normal cases. However, adjust
these values if it takes too a long time to reach the target tension when starting the system, changing the
tension settings, etc.
[1] Additional gain
[2] Dead zone width
• Setting screen
• The proportional gain corrects the output in proportion to the deviation between the target
tension value and the operating tension value.
• When a large value is set, the target tension is reached faster but fluctuation easily occurs.
• Setting range - - - -0 to 100% - - - - Initial value = 50%
• When this value is changed by +12%, the correction of output will be twice as larger as the
previous correction.
• The integral time determines the time responsibility against the deviation between the target
tension value and the operating tension value.
• When a small value is set, the controllability is improved but fluctuation easily occurs.
• When a large value is set, the control is stabilized but the response at the time when the unit
is activated, the tension set value is changed, etc. is deteriorated.
• Setting range - - - 0 to 100% - - - - Initial value = 50%
• When this value is changed by +12%, the time constant will be twice as large as the previous
value.
• If the current tension value is out of the dead band width of the target tension, the additional
gain set here will be added to the proportional gain.
• When a large value is set, the time required until the deviation enters the dead band range
can be made shorter. However, if the set value is too large, fluctuation easily occurs. Enter a
value with which appropriate response can be obtained when combined with the dead band
width and the proportional gain.
• Setting range - - - - - 0 to 100% - - - - Initial value = 0%
• The dead zone width specifies the deviation between the current tension and the target
tension generated when the proportional gain is changed over.
• When a small value is set, the additional gain will be added to the proportional gain for a
longer time, and the responsibility becomes faster but fluctuation easily occurs.
• Setting range - - - - - 0 to 50% - - - - - Initial value = 50%
("±%" of full-scale tension value)
- - - - - - - Item number : 40
- - - - - - - -Item number: 41
5.5 Adjustment of control gain
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