DFE SteadyWeb, Instruction Manual

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5.13 RATIO UP/DOWN (See Page 4 for description, Figure 16 for adjustments)
NOTE : The Ratio function is not normally needed for most applications. Use it only if there is a large
tension fluctuation during or directly after the splice.
The output of the controller is locked (see Section 5.17 Sample and Hold following) and then multiplied
or divided when an external contact is closed. The output will remain at this modified level as long as
the contact remains closed. When it opens, the controller goes into the AUTO control mode, after a
time delay. The amount of multiplication or division, called the ratio, is set by the RATIO pot. (RT108).
When the pot. is at midrange, the ratio is 1. When it is fully CCW, the ratio is 0.1. When it is fully CW,
the ratio is 10. The time delay is set with the RATIO DLY pot (RT117). When fully CW, the delay is
about 5 seconds. There is no delay at the fully CCW position. When the Ratio function is active, both
the Sample & Hold and the Ratio lights on the front panel will be illuminated.
a) To set the RATIO and RATIO DLY pots. it is necessary to operate the machine and record the
output of the controller at both core and full roll diameters. Use the output meter on the front panel
for this.
b) Turn the RATIO pot. 1/2 turn CW. Turn the RATIO DLY pot. 1/2 turn CW.
c) Connect the external contact as shown below.
Figure 21 - RATIO CONTACT ELECTRICAL CONNECTIONS
d) FOR UNWINDS: Run the machine slowly with the controller in the AUTO mode and set the tension
the same as it was when the core and full roll outputs were measured previously. Start at core
diameter. Make the following adjustment before many wraps accumulate on the core.
e) Close the external Ratio contact to put the controller in the Ratio mode. Turn the RATIO pot. CW
until the output meter reads the full roll value recorded earlier.
f) Perform a flying splice. Adjust the RATIO DLY pot. as needed to keep the controller in the Ratio
mode just long enough for the new roll to tag onto the web at the slowest machine speed at which
splices will be made.
g) FOR REWINDS: Wind a full roll of material. Then run the machine slowly with the controller in the
AUTO mode and set the tension the same as it was when the core and full roll outputs were
measured previously. Make the following adjustment at the full roll diameter.
h) Close the external Ratio contact to put the controller in the Ratio mode. Turn the RATIO pot. CCW
until the output meter reads the core diameter value recorded earlier.
i) Perform a flying splice. Adjust the RATIO DLY pot. as needed to keep the controller in the Ratio
mode just long enough for the web to tag onto the core at the slowest machine speed at which
splices will be made.