btsr IS3F-485, Руководство по эксплуатации

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Operation
- 3.8 - SMART KNIT
The suggested values for different yarns are as hereafter indicated:
Very thick yarns
1
Thick yarns
3
Medium yarns
5
Fine yarns (single filament yarn)
6-8
Very fine yarns (Lycra®)
9-10
Reaction time
(DELAY)
The DELAY parameter allows the adjustment of the sensor to the characteristics of
yarn to be processed
(e.g. elasticity) , by defining the Reaction Time of the sensor
before signaling a defect. It is possible to program 8 pre-set values:
5 ms - 10 ms - 20 ms - 50 ms - 100 ms - 200 ms - 500 ms - 1000 ms
# 50 ms is the suggested value for very high running speed of the yarn.
# 200 ms is the suggested value for normal yarns.
# 500 ms is the suggested value for elastic yarns.
Start Frequency
(F_START)
This parameter indicates the minimum frequency of image variation, beyond
which the sensor signals that the yarn is running normally
(green LED ON).
It can be programmed to a value ranging between 1 and 10 .
Stop Frequency
(F_STOP)
This parameter indicates the minimum frequency of image variation, below which
the sensor signals that the yarn runs normally
(red LED ON).
It can be programmed to a value ranging between 1 and 10 .
Programming examples for F_START/F_STOP and relevant sensor delays
As the diagram shows, if the F_START and F_STOP value is set low (e.g. = 2) ,
then the sensor could detect the condition of “running yarn” even though the yarn
is actually still or broken, and is undergoing a light oscillation
( A and B areas of
the diagram) . Otherwise, if a higher value is set (e.g. = 5) then the image variation
of A and B areas is not considered sufficient to detect the condition of “running
yarn”. It must be observed, however, that if the yarn detected by the sensor has a
very regular profile
(e.g. Lycra® or single filament yarn) , the frequency of the
image variation is lower; therefore if a value too high is programmed, the sensor
could not detect the “running yarn” condition
(or it would detect it with excessive
delay) . This is why the F_START and F_STOP values can be “calibrated”
according to the article to be processed, in order to obtain the condition of optimal
detection for that particular article.
! In the presence of frequent errors detected by the sensors, it is suggested to
gradually change such values until an optimal condition is achieved.