btsr IS3, Operating Manual

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Operating
SMART 3000TW - 3.7 -
Settings that affect the sensor detection features
The IS3.. series sensors are not simply detecting the presence of the yarn, but they
are working as true micro-computers. They provide a digital signal output, which
reflects the condition of the yarn within the detection area:
! Normal yarn running condition
! Yarn stopped or broken condition
The functioning of the sensor is based on the principle of variation of the image
relative to the shape of the yarn, detected by the tiny “camera”, which is
implemented inside the sensor. Such a variation of image
normally occurs only if
the yarn is in actual movement inside the detection area, i.e. only if the yarn is
running.
Nevertheless, in certain cases, there may be some variation of image even though
the yarn is not running normally, this is the case of a broken yarn oscillating inside
the detection area.
Finally there are other factors that can affect the detection activity of the sensors,
like the size and type of yarn
(silk, wool, acrylic, Lycra®, single filament nylon) , as
the variation of the image depends on these factors as well.
That’s why the microcomputer embedded in the sensor, processes the images
provided by the “camera” by means of the sensor memory, which takes into
account also these other influencing factors.
The variables of this program are represented by the settings connected to the
article, which is being worked, i.e.
! Start Frequency (F_START)
! Stop Frequency (F_STOP)
! Sensitivity (SENS)
! Reaction Time (DELAY)
Start Frequency (F_START)
This setting indicates the minimum frequency of image variation, beyond which
the sensor signals that the yarn runs normally
(green LED ON).
It can be programmed to a value between 1 and 10 .
Stop Frequency
(F_STOP)
This setting 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 between 1 and 10 .