Requirements for use
The output signals of the protective device must be analyzed by downstream controllers
in such a way that the dangerous state of the machine is ended safely. Depending on
the safety concept, the signal is analyzed by, e.g., safety relays or a safety controller.
DANGER
Hazard due to lack of effectiveness of the protective device
In the case of non-compliance, it is possible that the dangerous state of the machine
may not be stopped or not stopped in a timely manner.
b
Make sure that the following control and electrical requirements are met so that
the multiple light beam safety device can fulfill its protective function.
•
It must be possible to electrically influence the control of the machine.
•
The electrical control of the machine must meet the requirements of IEC 60204-1.
•
Depending on the regulations which apply at the place of installation, a restart
interlock may be required. Because the multiple light beam safety device does not
have this function, it must be implemented in the external control if required.
•
When using a safety controller, different signal levels of both OSSDs must be
detected depending on the regulations which apply at the place of installation or
the required reliability of the safety function. The maximum discrepancy time toler‐
ated by the control must be selected according to the application.
•
The OSSD1 and OSSD2 output signals must not be connected to each other.
•
In the machine controller, the signals of both OSSDs must be processed sepa‐
rately.
Figure 11: Dual-channel and isolated connection of OSSD1 and OSSD2
•
The machine must switch to the safe state at any time if at least one of the two
OSSDs switches to the OFF state.
•
Prevent the formation of a potential difference between the load and the protec‐
tive device. If you connect loads to the OSSDs (output signal switching devices)
that then also switch if controlled with negative voltage (e.g., electro-mechanical
contactor without reverse polarity protection diode), you must connect the 0 V con‐
nections of these loads and those of the corresponding protective device individu‐
ally and directly to the same 0 V terminal strip. In the event of a fault, this is the
only way to ensure that there can be no potential difference between the 0 V con‐
nections of the loads and those of the corresponding protective device.
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PROJECT PLANNING
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O P E R A T I N G I N S T R U C T I O N S | deTem4 Core
8020453/14Q7/2020-04-27 | SICK
Subject to change without notice
