Emerson Vilter Vission 20/20, Руководство по эксплуатации и обслуживанию

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24 – 3
Section 24 • Twin Screw Control
Vission 20/20 • Operation and Service Manual • Emerson • 35391SC 2.7
Figure 24-3. Slide Calibration - Continuous VI
Software limit setpoints
The Vission 20/20 uses the “Min Limit” and “Max Limit”
setpoints to define an area within the mechanical stops
for normal slide travel. These software limits’ purpose is
to prevent the slide from actually hitting the mechani-
cal stops which could result in a number of undesirable
consequences. By default, the software limits are set to
150mV from either end point. The position percentage is
calculated from the software limits. Therefore, it is pos-
sible to read a value greater than 100% or less than 0% if
inertia carries the slides after these limits are reached.
Fixed VI:
• The normal software limits apply without any
modification.
Continuous VI:
• “Max Limit” when VI is maximum will be different
from “Max Limit” when VI is minimum. Max limit
(Min VI)‘s value will be greater than Max Limit (Max
VI)’s value. The default value for Max Limit (Max VI)
is 3440.0 and the default value for Max Limit (Min VI)
is 4850.0
Step VI:
• Max limits for Step 1, Step 2 and Step 3 will be dif-
ferent. Step 1’s Max Limit will be greater than Step
2’s Max Limit which will be greater than Step 3’s Max
Limit.