Omron Sti F3SJ-B P25-01TS Series, User Manual

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16
Chapter
2
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F3SJ-B
User’s Manual
System Configuration and Functions

External Device Monitoring Function
This function detects malfunctions, such as welding, in external relays (or contactors) that control the
hazardous part of a machine.
This function constantly monitors that a specified voltage is applied to the receiver's external device
monitoring input line, and the system enters lockout state when an error occurs. The relay's
operational delay can be up to 0.3 s without being evaluated as an error.
For example, if the normally closed N.C. contact does not close within 0.3 s after the safety outputs
turn from ON to OFF, and a specified voltage is not applied to the external device monitoring line , it is
evaluated as an error and the system enters a lockout state.
To utilize this function properly, use safety relays and contactors that have force guided or
mechanically linked contact structure.
 Wiring
Perform wiring so that a voltage of Vs-3 V to Vs is applied to the external device monitoring line via the
external relay's normally closed N.C. contact.
When external device monitoring is not being used, apply the auxiliary output to the external device
monitoring input.
Wiring for external device monitoring function p.10
 Timing chart
The sensor reads out a device monitoring input value a minimum of 0.5 s after the power of the F3SJ-
B is turned ON. If the status of the safety outputs is changed back to the original status within the
allowable delay time, the F3SJ-B will not enter the lockout state.
Safety output
ON
OFF
External device
monitoring input
ON
OFF
Unblocked
/Blocked
Unblocked
Blocked
Lockout
T = 0.3 s
0.3 s
Within 0.3 s