Rockwell Automation WebPak 3000 DC Drive Application Workbook Version 1.1 - Manual (Page 60)

10-4 WebPak 3000 DC Drive Application Workbook, Version 1.1
Note that TENSION VERNIER (P.856) will be a proportional or incremental trim of line
speed dependent on the configuration of OCL PROP TRIM SELECT (P.813). Refer to
section 3.3 and figure 3.1.
þ
To set the PI block HI and LO limits:
▲
Set TENSION PI LIMIT (P.853). For example, if 10% tension vernier is to be used,
set the PI block HI and LO limits to 409 counts.
The output of the tension PI block provides a vernier signal that is used to trim
the speed loop reference when OCL TYPE (P.818) is set to CASCADE and to trim
the speed loop PI limits when OCL TYPE (P.818) is set to PARALLEL .
In cascade, 4095 counts equals top line speed. In parallel, 4095 counts
equals maximum current.
þ
If the outer control loop is configured as a current regulator
(P.817 =
CURRENT ):
▲
Set TEN LEADLAG SELECT (P.837) to BYPASS .
10.5 The Slack Take-Up Function
The slack take-up function initiates a smooth removal of loose web, when drive
tension is on, by limiting the amount of motor torque applied until the slack is removed.
When slack take-up is released, the drive operates at the tension set by TEN RAMP
OUTPUT (P.842). Refer to figure A.19 in Appendix A of the software manual (D2-3444).
þ
To use the slack take-up function:
▲
Set SLACK TENSION PI LIM (P.318).
▲
Assert the slack take-up digital input (terminal 12 on the Regulator board).
(
SLACK TAKE UP DIN TP (P.494) should be ON .) The drive uses the value of
SLACK TENSION PI LIM (P.318), which is a percentage of the running limit value
as set by TENSION PI LIMIT (P.853).
þ
To turn off the slack take-up function:
▲
De-assert the slack take-up digital input (terminal 12 on the Regulator board).
(
SLACK TAKE UP DIN TP (P.494) should be OFF .)
Range: 0 to 4095 COUNTS P.853 = COUNTS
Range: LEAD / LAG , BYPASS , LAG / LEAD P.837 =
Range: 0.0 to 100.0% P.318 = %