Rockwell Automation 9329 Drive Application Software Tension Control Gen. Units - Manual (Page 12)

FM – Tension Control
Drive Application Software – page 12 of 52
4.0 Functional Description
4.1 Overview
The Tension Control Function Module calculates tension torque requirements and supports
web tension control with dancer position feedback, load cell feedback, and without tension
feedback. The Tension Control Function Module consists of a program with five routines in
RSLogix 5000. These routines are dependent on one another and typically should not be
separated.
1. Main (Ladder)
2. Logic (Ladder)
3. Regulator (Function Block)
4. TenRfTaper (Function Block)
5. TrqMem (Function Block)
The user may edit the Main routine to connect signals (tags) and configure the FM. The user
cannot edit the remaining routines. The Tension Control Function Module is unit less in
design. The modules outputs will reflect the inputs applied to module. The units applied to
the module must be consistent. DO NOT mix imperial and metric units.
4.1.1 Main routine
The Main routine is where the user connects user created controller tags to the input
and output program tags of the FM. These links are created in the Jump to Sub-
Routine (JSR) instructions. A unique JSR is used for each subroutine (Logic,
Regulator, TenRfTaper, & TrqMem).
4.1.2 Logic routine
The Logic routine is used to configure and control the tension regulator. The user
configures the Function Module based on what type of control (load cell, dancer, or
open loop torque). The user enters machine specific information such as gear ratio,
rated motor torque, etc.
4.1.3 Regulator routine
The Regulator routine controls either the position of the dancer; the tension utilizing a
load cell for feedback, or the open torque. This routine is also responsible for
selecting either run tension reference or stall tension reference and ramping the
selected reference to the final value.
4.1.4 TenRfTaper routine
The TenRfTaper routine adjusts the tension reference based on roll diameter. As the
material builds up on a winder, the tension reference is reduced to prevent material
damage. This routine performs linear taper. If a profiled taper circuit is required, the
user may delete this routine and generate their own control circuit.
4.1.5 TrqMem routine
The TrqMem routine is used to hold torque reference when transferring tension
control between two Center Winders. Once the web is cut from the expiring roll, the
incoming roll transfers into tension control.