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Dancer control detail
3.7 Dancer control detail
3.7.1
PID setting (Pr. 128 to Pr. 130, Pr. 134 to Pr. 137, Pr. 709, Pr. 710)
(1) PID action selection
(Pr. 128)
Set forward or reverse action according to the control target.
Set point/dancer signal/main rotation speed command for the dancer control function (
Pr. 128
= 40, 41) are indicated in the
following table.
* Use
Pr. 731 Dancer signal input selection
to change the signal input.
(Refer to page 27)
(2) PID control proportional band
(Pr.
129)
If the proportional band is narrow (parameter setting is small), the manipulated variable varies greatly with a slight change
of the dancer signal.
(3) PID control differential time
(Pr. 130)
Ti is the time required for the integral (I) action to provide the same manipulated variable as that for the proportional (P)
action.
As differential time becomes less, set point can be reached faster.
POINT
Turn X83 signal ON to perform dancer control and winding diameter compensation.
When X83 signal is OFF, dancer control and winding diameter compensation are not performed.
It may be necessary to perform dancer control with winding diameter compensation disabled (winding diameter is retained)
for intermediate shafts. In such case, turn ON X83 signal and X84 signal together, or set
Pr. 771
= "9999" (no winding
diameter calculation.)
Set "83 (X83)" and "84 (X84)" in
Pr. 178 to Pr. 189 (input terminal function selection)
to assign X83 and X84 signals.
Pr. 128
Setting
Forward/
reverse action
Set point
Dancer signal *
Main rotation speed command
40 (Initial value)
Reverse action
Pr. 133
Terminal 1
(Initial value)
Same rotation speed command with normal
operation speed selection.
41
Forward action
PID control formula: G
Kp (1+
1
+ Td
S)
Ti
S
Gain Kp = 1/proportional band
Gain G = PID gain selection function : refer to
page 30
Pr. 130
(PID control integral time) is multiplied by:
S in
1
of
Ti
S
the PID control formula
G
Kp (1+
1
+ Td
S)
Ti
S
