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The principle of operation is as a one way light barrier. By activating the safety edge, the
photo-beam will be interrupted.
Typ 3: Optical safety edge (Vitector)
Typ 2: Resistance evaluation 8K2 with normally open safety edge contact
This evaluation system is made for electrical safety edges within an end-of-line resistor of
8K2 -+ 5% 0,25W. The resistor must be connected parallel with the switch in the safety edge.
This evaluation system is made for pressure-wave switches (N/C) within an end-of-line
resistor of 1K2 +/- 5% 0,25W.
A pressure wave is generated by compressing the rubber profile, which is conducted to the
pressure-wave switch through the plastic hose. The system should be tested in the CLOSE
position. The pre-limit would be set automatically and activate the "Testing function".
When the shutter runs over the pre-limit door position, a timer of two seconds starts to
countdown at once. If a pressure wave activates the pressure switch in this time the TS
970 recognizes the function of the safety edge. If the pressure switch has not been activated,
the control goes into fault mode and the system works only in DEAD MAN function in
downwards direction. Fault information F 2.8 would be displayed.
Typ 1: Resistance evaluation 1K2 with normally closed safety edge contact
Pressure-wave switch - function
The contact between the contact screw and
diaphragm is opened (opening contact). The
pressure-wave switch is set to a release pres-
sure of approx. 1,5 mbar.
The valve screws are set to a throughput of
110 ml/min with a static admission pressure
of 5 mbar. This warrants that a maximum tem-
perature increase of 30° is compensated for in
20 minutes.
The setting of the valve screws may not be
altered. Should the release pressure be insuf-
ficient (pressure wave too insensitive), the
contact screw may be turned counterclock-
wise to the left by 1-2 graduation marks. The
switch's sensitivity is thus increased.
In case of excessive sensitivity, the contact
screw is set clockwise by 1-2 graduation
marks (decreased sensitivity).
Pressure-wave switch
valve screws (may
not be altered)
Hose contact for :
pressure opens
contact screw
SAFETY DEVICES
