External Device Monitoring (Edm) - Omron G9SP Series Reference Manual

Safety Device Function Blocks
3-5-1

External Device Monitoring (EDM)

Basic Function
Diagram
General Description
Startup
Set Parameters
Maximum Feedback Time
(T
Note
Optional Output
Settings
The External Device Monitoring function block evaluates the input signal and
the status of an external device and outputs safety outputs to an external
device. This function block is used to detect fused contacts or external wiring
problems (disconnected lines) for safety relays, contactors, and other safety
devices.
Default
The External Device Monitoring function block evaluates the input signal and
the status of an external device and outputs safety outputs to an external
device.
If the Monitored Input signal turns ON, the Output 1 and Output 2 signals will
turn ON. When this occurs, the status of the EDM Feedback signal must turn
ON within the specified time.
If the Monitored Input signal turns OFF, the Output 1 and Output 2 signals will
turn OFF. When this occurs, the status of the EDM Feedback signal must turn
ON within the specified time.
If the status of the feedback signal does not change within the specified maxi-
mum feedback time, an EDM error will occur, the Output 1 and Output 2 sig-
nals will turn OFF, and the EDM Error signal will turn ON.
All errors are turned OFF and all timers are reset at the start of operation.
Outputs are turned ON or OFF according to the input status.
Parameter
)
EDM
The timer SV must be longer than the cycle time.
If an ON/OFF-delay function block is placed after an EDM function block or an
ON/OFF-delay is set for a safety input terminal that inputs EDM feedback, set
the value taking those values into consideration.
The following outputs can also be used in programming. To enable either of
these optional outputs, select the check box on the Output Point Tab Page of
the function block properties dialog box.
• EDM error
• Output 2
Output 2 performs the same operation as output 1.
Maximum Number of Outputs
Setting range
100 to 1000 ms in 10-ms increments
Section 3-5
Default setting
300 ms
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