Nexen TC920V 964356 - Manual (Page 33)

30 FORM NO. L21268-C-1013
8. UNIT OPERATION (continued...)
8.2 WINDING APPLICATION
A typical winding application begins with a roll at core. Prior to the Auto Trigger contact while the unit is in standby, the
START indicator is lit, and the control output is set to the Start Level. The Start Level should be set high enough to
prevent bagging while the machine beings to accelerate. During the start phase, the control output will typically be lower
than the control level during the automatic mode to mitigate against a web break as the roll inertia accelerates. After the
expiration of the Start Timer phase, the AUTO lamp will be lit and the control output is under automatic control and the
tension should stabilize at the tension set point. Many winders are started before the machine begins to move the web.
When the winder is started before the machine, the Start Time should be set to zero so that the machine starts immediately
under automatic tension control. Taper tension can also be used to taper the winding tension as the roll diameter builds
in cases where a higher tension winding is required near core.
During the stop phase, the Stop Level multiplier increases the control output. During the stop phase, the measured tension
can be higher than the tension set point, depending on the stop level. The Stop Level compensates for the decelerating
roll inertia, and is set high enough to prevent bagging in the web, but low enough as to not cause a weak break. The STOP
lamp will indicate during the stop phase, after which the START lamp will be lit indicating the unit is in standby and the set
Start Level is applied to the control output.
FIGURE 8.2 Typical Winding Operation
Start Auto Stop Start Auto Stop Auto
Auto Contact
T
1
T
1
T
2
T
2
Contr
ol Output / T
ension L
evel
Control Output
Tension Level
T
1
: Start Time
T
2
: Stop Time
Front Panel
Indicator