Tension Macro; Close Lp Spd - ABB ACS800 Series Firmware Manual

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Tension macro

The purpose of tension regulation is to control the surface web tension as material is
wound or unwound. This is achieved by using loadcell tension feedback.
Differences between the tension setpoint and the loadcell feedback allow the tension
PI regulator to develop the error correction needed to maintain tension by trimming
either speed or torque of the driven section. The tension PI regulator is updated
every 10 ms to produce very responsive trim.
The P-Gain of the tension regulator is adaptive for roll diameter changes. As the
diameter of the roll increases, the P-Gain can be set to increase from a min. P-Gain
at core diameter to a max. P-Gain at full roll. If the adaptive P-gain is not desired, the
min. and max. parameters can be set the same.
When running in Speed Trim, the tension regulator is very adaptable to a large
variety of web material characteristics and should be used in applications where stall
tension is required.
A winder application can optionally be operated in Torque Trim. When running in
Torque Trim, an encoder is typically required. If stall tension is required, speed trim
is recommended. When using Torque Trim, accurate web material information is
required for calculating the inertia torque value of the roll, thus making it less
adaptable to a wide variety of materials. However, Torque Trim may result in more
stable steady state performance. Open-Loop Tension regulation can be achieved by
selecting torque control and Torque No Trim. See
MODE TRANSITION. Loadcell feedback is not required in this type of operation. The
drive will calculate the required torque based on tension setpoint, roll diameter,
frictional losses, and gearing to achieve the proper tension on the Web. In open loop
tension mode, the overspeed reference is 50 rpm or 10% of the speed reference
(whichever is greater), this is not adjustable.

CLOSE LP SPD

The drive is speed controlled and uses the loadcell feedback to regulate the web
tension to the setpoint. To properly operate in this mode the following parameters
must be set up:
63.05
63.06
63.09
63.10
63.11
63.12
63.13
63.14
63.15
63.16
Application macros
RANGE ADJUST
TRIM REG REL TO
TENSION CTL ENABLE - must be active for the PI regulator to operate
TENSION SETPOINT
TENSION FDBK INPUT
TAPER REF SELECT
MAX TAPER/%TAPER - if no taper is desired, set this to 0%
MAXIMUM TENSION
TENSION MODE - must be "CLOSE LP SPD"
MODE TRANSITION - do not want transition to be active
63.15 TENSION MODE and 63.16