Procedure For The Calculation Of The Starting Diameter - GE AV-300i User Manual

GEH-6641E

1.15.7.2 Procedure for the Calculation of the Starting Diameter

Such calculation is based on the measurement of the dancer moving from its lower limit switch position to its
central working position, and on the measurement of the winder angular moving during the initial phase.
For this reason during such period the dragging at the unwinder end or at the winder beginning must be in a
position to keep the material blocked. To this purpose it is necessary to enable the dragging Drive regulation
with a speed reference = 0.
If also the line nip rolls are controlled by dancers or loading cells, it is necessary to carry out first the diameter
calculation with the following winder and unwinder initial phase and afterwards the dragging initial phase.
The PID MlpPI sel parameter must always be equal to 0 in order to avoid that PID PI out mon is set with a
predefined value.
By setting the source of DiaClc start src to one and if the Drive is enabled, the procedure is started.
During this phase the parameters and the PI and PD regulators are disabled.
The regulation checks the signal coming from the dancer potentiometer.
If this value is higher than the one set in Max deviation, the motor starts rotating with the speed reference set in
Positioning spd in order to wind the material on the winder and to bring the dancer into its central working
position.
If the regulation checks that the signal coming from the dancer potentiometer is lower than the value set in Max
deviation, the motor starts rotating with the speed reference set in Positioning spd in order to unwind the
material and to bring the dancer to the point identified by Max deviation.
At this point the reference is inverted till bringing the dancer in its central working position.
When the dancer has reached its central position, the PID PI out parameter is initialized with the value of the
measured diameter.
The Diacalc active variable brings to a high logic level the Diameter calc st digital output, stating the end of the
diameter calculation phase.
Now, if the PI and/or PD blocks are enabled, the system reaches automatically the regulation mode.
To this purpose the digital inputs programmed as DiaClc start for the PI and PD enable are brought simulta-
neously to a high logic level.
The Diacalc active output signal can be used to reset the DiaClc start command (such command is activated on
the climbing leading edge of the digital input; for this reason it has to be brought to a high level after power
supplying the Drive regulation section and it has to be reset when the starting calculation phase is over).
The value of PID PI out is calculated via the following formula:
PID PI out = (Minimum diameter x PI clamp top) / value of the calculated diameter
The PI clamp top and PI clamp bot parameters of the PI controls menu have to be set according to the
maximum and minimum winder diameter.
Ch.1
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