Nexen RSTC1100 964528 - Manual (Page 14)

FORM NO. L-21204-C-0908 14
ALARMS
NOTE: A web break is detected whenever the web
tension falls below 10% of the Maximum Tension
Setpoint Alarm 1 is used to signal the break.
Tension Tolerance: Enter the tolerance (0–100 %) of
the tension setpoint to establish the limits for the High
Tension and Low Tension alarms. For example, if Tension
Tolerance is set to 10 and the Tension Setpoint was 100,
then the High Tension alarm would be activated if the web
tension exceeded 110 and the Low Tension alarm would
be activated if the web tension fell below 90. These alarms
utilize Alarm 2 to signal their condition.
Alarm Outputs: Select if the alarm outputs are to be
normally open (NO) or normally closed (NC). A normally
open output will close during an alarm condition while a
normally closed output will open.
WEB
Max Diameter: Enter in the maximum full roll diameter that
will be used. For mid-process tension control applications,
enter 1.1 multiplied by the nip roller diameter.
Min Core Diameter: Enter in the minimum core diameter
that will be used. For mid-process tension control
applications, enter the diameter of the nip roller.
Avg Web Width: Enter in the average web width [(maximum
width + minimum width) / 2].
Material: Select the web material to be used: Paper or
Plastic, Steel, or Aluminum from the drop down menu
(See Figure 14).
OUTPUTS
Minimum Output %: Used to specify a minimum output
level, typically set to 0 %. Minimum Output is often set to
a value greater than zero in order to overcome the spring
force in brakes and clutches that are spring disengaged.
Maximum Output %: Used to specify the maximum output
level, typically set to 100%.
Standby Output %: Used to specify the output level in
standby mode (not controlling tension). Standby Output
is often used in splicing unwind applications when it is
desired to have some brake drag on the make ready roll.
Tension Monitor: Select ON and Control Output B
will output web tension monitor signal or select OFF
and control Output B will output web tension control
signal (See Web Tension Monitor in INPUT/OUTPUT
DESCRIPTIONS section).
Figure 14 Web Material Selection Screen