8.4 Measures taken to minimize the possibility of defeat
To complicate simple defeating of the fail-safe sensor the following
measures have been taken:
1. By slowly approaching a metallic object the enable zone is indicated
with the signal LED after a delay of approx. 3 s (but the outputs
are triggered without delay) so that the object is normally in the
close zone before this display becomes active. The technical
instructions concerning the restart of the installation must be observed.
2. If the metallic object remains in the close zone for over approx. 2 s,
the outputs are completely disabled and no longer enabled in case
of damping in the enable zone. If the object stays longer than approx.
5 s in the close zone, the adjustment mode is activated (see 9.2
Adjustment).
The enable zone is enabled
• by undamping (> 30 mm) for over 2 s
• or by interrupting the voltage
(also see 9.2 Adjustment).
The statements under points 3. and 6. are to be taken into account.
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