Mitsubishi Electric A800 Plus Series Function Manual page 173

Winding diameter calculation setting
Initial winding diameter calculation at a start (enabled under Vector
control only)
• Calculate the initial winding diameter "D" from the dancer travel distance "L" when the dancer roll moves from the lower limit
position to the neutral position at a start.
D =
• When Pr.1255 Accumulated amount = "8888" and the dancer roll position is equal to or lower than the setting of Pr.1252
Dancer lower limit position, dancer roll is lifted with PI gain at a start, but initial winding diameter calculation is not
performed. This operation is useful to wind up sagging material slowly.
• When Pr.1255 = "9999", winding diameter calculation is not performed, and the winding diameter, which has been used, is
kept. In such a case like this, PI gain of speed control for normal operation is used instead of gain for winding diameter
calculation.
Pr.1255 setting
1 to 5000 mm
8888
9999
NOTE
• Do not use Pr.78 Reverse rotation prevention selection when using initial winding diameter calculator function.
• To adjust the overshoot amount at an initial winding diameter calculation, use Pr.73 Analog input selection to set the
polarity reversible operation.
• To minimize fluctuation of the dancer roll when shifting from initial winding diameter calculation to normal operation, set Pr.13
Starting frequency = "0".
Dancer lower limit position and accumulated amount setting (Pr.1252,
Pr.1255)
• Set Pr.1252 Dancer lower limit position and Pr.1255 Accumulated amount. The winding diameter at a start is
calculated from the dancer roll travel distance (accumulated amount) and the corresponding number of pulses (number of
rotations).
172
WINDING DIAMETER COMPENSATION FUNCTION
2  L
π  N  Z
When the dancer roll position is equal to or
lower than the Pr.1252 setting
• Initial winding diameter calculation is performed.
• The winding diameter obtained from the initial
winding diameter calculation is used.
• The dancer roll is lifted with PI gain (Pr.1256 to
Pr.1259) at a start.
• Initial winding diameter calculation is not performed.
• The winding diameter is kept.
• The dancer roll is lifted with PI gain (Pr.1256 to
Pr.1259) at a start.
• Initial winding diameter calculation and dancer lifting
operation are not performed.
• The winding diameter, which has been used, is kept.
Target position
L
Lower limit position
Pr.1255=2×L
L : Dancer travel distance (accumulated amount = 2  L)
N : Number of motor rotations
Z : Gear ratio
When the dancer roll position is higher than
• Initial winding diameter calculation and dancer lifting
operation are not performed.
• The winding diameter, which has been used, is kept.
• Initial winding diameter calculation and dancer lifting
operation are not performed.
• The winding diameter, which has been used, is kept.
• Initial winding diameter calculation and dancer lifting
operation are not performed.
• The winding diameter, which has been used, is kept.
the Pr.1252 setting