Safety Sensors - Lenze i550 Series Project Planning Manual

Safety sensors

The components used must comply with the risk reduction required for the application.
Active sensors
Active sensors are units with 2-channel semiconductor outputs (OSSD outputs).
Test pulses for monitoring the outputs and lines are permissible.
P/M-switching sensors switch the positive and negative cable or the signal and ground cable
of a sensor signal.
Please note the following:
The maximum permissible connection capacity of the outputs.
•
Active sensors are connected directly to the terminal strip, see section "Active sensor con-
•
nection".
Monitoring for short circuits must be carried out by the active sensor.
•
The outputs have to switch simultaneously (equivalently). Safety functions will be activated if
only one channel is switched. Active triggering of only one channel points to faulty sensors or
impermissible wiring.
Examples of active sensors:
Lightgrid
•
Laser scanner
•
Control systems
•
Passive sensors
Passive sensors are 2-switching elements with contacts.
Please note the following:
The switches must be wired according to the closed-circuit principle.
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Passive sensors are connected to the terminal strip via a safety switching device, see sec-
•
tion "Passive sensor connection".
The connecting cables and the sensor function must be monitored by an external safety
•
component.
The contacts must switch simultaneously (equivalently). Safety functions will be activated if
only one channel is switched. Switching of only one channel points to faulty sensors or imper-
missible wiring.
Examples of passive sensors:
Door contact switch
•
Emergency stop control units
•
Product extensions
Functional safety
Safety sensors
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