No Potential Difference Between Load And Protective Device - SICK deTec4 Core Vibes Operating Instructions Manual

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PROJECT PLANNING
26 O P E R A T I N G I N S T R U C T I O N S | deTec4 Core Vibes
Figure 17: No potential difference between load and protective device
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 applic‐
able national regulations or required reliability of the safety function.
Make sure that downstream contactors are monitored (external device monitoring,
b
EDM).
Because the safety light curtain does not have integrated external device monitor‐
b
ing, this must be implemented in the external control, if required.
Requirements for the electrical control of the machine
The two outputs are short-circuit protected against 24 V DC and 0 V. When the protec‐
tive field is clear, the OSSDs are in the ON state and the signal level is HIGH (non-iso‐
lated). In the event of an interruption in the light path or device fault, the OSSDs are in
the OFF state and the signal level is LOW (above 1.5 kΩ to 0 V).
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.
Make sure that the following control and electrical requirements are met so that
b
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,
see "Accessories", page 62.
8024467/2019-06-18 | SICK
Subject to change without notice