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Contrinex Industrial Electronics
SCOPE OF THIS TECHNICAL DOCUMENTATION
This section contains useful information for the selection, installation,
operation and maintenance of Safetinex light curtains and access con-
trol barriers. It is intended for skilled personnel with a knowledge of
safety issues and electronic equipment. For safety compliance of your
installation, please refer to the relevant standards and directives.
OPERATING PRINCIPLE
Safetinex light curtains and access control barriers are optoelectronic
safety devices that include a sender and a receiver unit between which
coded infrared beams are sequentially exchanged. The receiver unit is
connected to a safety relay which transmits signals to the machine con-
trol system. Synchronization between the sender and receiver devices
is performed optically, i.e. wired connection between the two units is
not necessary.
Reception of all beams activates the two independently generated
semiconductor outputs (OSSDs) of the receiver unit. The interruption
of one or more beams deactivates the outputs within the response time
of the AOPD. Any internal fault is detected by the device’s permanent
self-control function and has the same result as an intrusion into the
protective field.
SELF PROTECTED OUTPUTS
Both OSSD1 and OSSD2 are self-protected and actively monitored PNP
outputs. Both outputs are controlled by independent current-monitored
high-side switches. Thanks to continuous monitoring, any short-circuit
between an output and the power supply or ground is detected, leading
to the deactivation of the other output. Similarly, a cross-circuit between
the two outputs is also detected and both OSSDs are deactivated within
the specified response time. The OSSD outputs are switched off and
remain in that state as long as the fault remains.
FIG. 7: OPERATING PRINCIPLE
Emitter
Receiver
Synchronizing
beam
Resolution (R)
Pr
otective height
Operating distance (d)
