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Programming Your Application
6-29
590+ Series DC Digital Converter
DIAMETER CALC.
This block is used to calculate roll
diameters in winder applications.
The block is ignored by the drive unless the
DIAMETER parameter (Tag 431) in the
"BLOCK DIAGRAM" MMI menu is set to
a non-zero tag value. This is performed
automatically using ConfigEd Lite: when
the DIAMETER parameter in the
"DIAMETER CALC" block is connected to
another block, the destination tag value is
written to Tag 431.
DIAMETER CALC calculates the diameter of a reel as a function of the reel speed and the
line speed. The resulting diameter is a percentage of the maximum full roll diameter. A lead
section, adjacent line section, or surface driven speed sensing device is required to supply the
line speed signal. The winder or unwind drive's motor speed feedback provides the reel speed
input.
The ratio of the minimum core diameter to the maximum roll diameter determines the
operating range of the diameter calculator. Set MIN DIAMETER to that ratio using the
expression:
Minimum Core Outside Diameter
y
Maximum Full Roll Diameter x 100%
The magnitude of LINE SPEED is compared with MIN SPEED to determine when the
diameter calculator will operate:
x
When LINE SPEED is above MIN SPEED the calculator is on
x
When LINE SPEED is below MIN SPEED, DIAMETER is held at the last calculated
diameter
When EXTERNAL RESET is ENABLED, RESET VALUE is used as the diameter output.
Note:
In turret winder applications, LINE SPEED will usually be above MIN SPEED. During roll
changes, EXTERNAL RESET must be held ENABLED for the new spindle until the web has
been transferred and the diameter is calculated properly. RESET VALUE must be set to
the appropriate new core value for a rewind, or new roll diameter for an unwind.
RAMP RATE adjusts the filtering of the diameter output. Its setting is the time it takes for a
100% change in DIAMETER. For example, at the default setting of 5.0 seconds, a 50% step
change in diameter would take 2.5 seconds for the output diameter output to display the
change.
MMI Menu Map
1
SETUP PARAMETERS
2
SPECIAL BLOCKS
3
DIAMETER CALC.
LINE SPEED
REEL SPEED
MIN DIAMETER
MIN SPEED
RESET VALUE
EXTERNAL RESET
RAMP RATE
DIAMETER
MOD OF LINE SPD
MOD OF REEL SPD
UNFILT DIAMETER
Diameter Calc.
DIAMETER
[427]
–
0.00 %
MOD OF LINE SPEED
[428]
–
0.00 %
MOD OF REEL SPEED
[429]
–
0.00 %
UNFILTERED DIAMETER
[430]
–
0.00 %
0.00 %
–
[424] LINE SPEED
0.00 %
–
[437] REEL SPEED
10.00 %
–
[425] MIN DIAMETER
5.00 %
–
[426] MIN SPEED
10.00 %
–
[462] RESET VALUE
DISABLED
–
[463] EXTERNAL RESET
5.0 s
–
[453] RAMP RATE
Parameter
Tag
Range
DIAMETER
427
xxx.xx %
This is the output of the block and it can be connected to the appropriate points in the
winder block.
MOD OF LINE SPEED
428
xxx.xx %
(MOD OF LINE SPD)
Modulus of line speed.
MOD OF REEL SPEED
429
xxx.xx %
(MOD OF REEL SPD)
Modulus of reel speed.
UNFILTERED
DIAMETER
430
xxx.xx %
(UNFILT DIAMETER)
Unfiltered value of “diameter” (before RAMP RATE filter).
LINE SPEED
424
-105.00 to 105.00 %
This will usually be configured to be the analog tacho input and scaled appropriately during
calibration.