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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.
Downstream contactors must be positively guided and monitored depending on appli‐
cable national regulations or required reliability of the safety function.
b
Make sure that downstream contactors are monitored (external device monitoring,
EDM).
b
Because the safety light curtain does not have integrated external device monitor‐
ing, this must be implemented in the external control, if required.
Requirements for the electrical control of the machine
Both outputs are short-circuit protected to 24 V DC and 0 V. When the protective field
is clear, the OSSDs are in the ON state. When a switch-off condition is present (e.g.,
interruption in the light path), the OSSDs are in the OFF state. In the event of a device
fault, at least one OSSD is in the OFF state.
The safety light curtain complies with the rules for electromagnetic compatibility (EMC)
for the industrial sector (Radio Safety Class A).
Radio interference cannot be ruled out when used in residential areas.
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 safety light curtain can fulfill its protective function.
•
The external voltage supply of the safety light curtain must be capable of jumper‐
ing a brief power failure of 20 ms as specified in IEC 60204-1
•
The power supply unit must ensure safe isolation according to IEC 61140
(SELV/PELV). Suitable power supply units are available as accessories from SICK.
Further topics
•
4.4.1
Restart interlock
Overview
The restart interlock prevents the machine from automatically starting up, for example
after a protective device has responded while the machine is operating or after chang‐
ing the machine’s operating mode.
Depending on the regulations which apply at the place of installation, a restart interlock
may be required.
The protective device does not have an internal restart interlock. You must therefore
implement a restart interlock externally via the circuitry or the control if needed, e.g. in
connection with the SICK RLY3-OSSD2 / RLY3-OSSD3 safety relay.
Principle of operation
Before the machine can be restarted, the operator must reset the restart interlock.
PROJECT PLANNING
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8025644/19Z2/2021-03-09 | SICK
O P E R A T I N G I N S T R U C T I O N S | C4-RD
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Subject to change without notice