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3. General information and functional description
The compact and easy-to-install safety relay is designed for use on
controllers that are equipped with the appropriate plug base with
proper configuration.
The inductive signal transmission system solves the problem of
connecting moveable safety contact edges to a stationary evaluation
system without mechanical stress. Communication between the
moveable safety contact edges and the electronic evaluation system
is based on induction. To achieve this, the monitoring electronics
induce a frequency on a coil core, which is integrated in a closed
conductor loop.
The second coil core, to which the moveable safety contact edges
are connected, receives this frequency and sends corresponding
feedback to the electronic evaluation system in the event of cable
break or actuation of a safety contact edge.
Up to two moveable safety contact edge circuits that travel on the gate leaf can be connected to the switching
unit. These safety contact edge circuits are monitored by the signal transmission system contact- and wear-
free.
There are two types of safety contact edge circuits:“safety contact edges - opening movement“ and „safety
contact edges - closing movement“.
The switching unit continuously monitors these two safety contact edge circuits for actuation or interruption
(cable break). In the event of a fault, one of the two stop commands (stop in the opening direction or stop in
the closing direction) is issued to the respective safety contact edge circuit. A terminating resistor is integrated
into the end edge of the safety contact edge circuit in order to enable the standby current of the entire system
to be monitored. If the specified standby current is flowing, the open collector outputs relays are activated. If
a safety edge is actuated or the sensor circuit is interrupted, the respective „open collector outputs“ switch.
For increased safety, both output channels are fitted with two switching stages. The switching states of the
open collector outputs and the applied operating voltage are indicated by LEDs.
If an error is present, all the safety outputs are not active.
4. Proper use
The switching unit is intended to be used as protection in combination with safety contact edges with
integrated 8.2 KΩ resistor for standby-current monitoring on a gate system.
The switching unit can only fulfil its safety-related task if used properly.
Any uses above and beyond these uses constitute improper use. The manufacturer assumes no liability for
damages arising from improper use.
The device may only be used in special applications with the manufacturer’s express consent.
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English
INDUS onboard 70-755
Inductive signal transmission system