Short-Circuit Detection Function - Mitsubishi Electric MELSEC iQ-RX40NC6B Application User's Manual

Short-circuit detection function

This function detects an overcurrent of outputs and limits the output current.
When the output current is 20ms or higher, or 0.5A/point or higher, a short circuit is detected.
A problem has
A short circuit
occurred on C!
was detected on
a valve!
GX Works3
Operation of when an error is detected
When a short circuit occurs on the output terminal for which "Output short-circuit detection setting" is set to "To detect",
'Output short-circuit detection status' is set to 1 (Short circuit detected).
When the output module with diagnostic functions detects a short circuit, an alarm (Output short-circuit detection) occurs.
The output terminal with a short circuit stops the output.
The alarm status due to an output short-circuit detection can be checked in the module diagnostics window of the engineering
tool.
When a short circuit is detected, the ALM LED turns on.
Operation of when the connection is recovered from a short circuit
The operation of when the cause of a short circuit is eliminated and the connection with the external device is recovered
differs depending on the setting in "Short Circuit Auto Clear enable/disable".
■When "Short Circuit Auto Clear enable/disable" is set to "Disable"
The following shows the operation of when 'Alarm clear request' (Y11) is turned on and off.
• The value of 'Output short-circuit detection status' (Un\G3088) changes from 1 (Short circuit detected) to 0 (Normal).
• 'Alarm flag' (X11) turns off.
• The ALM LED turns off.
Short-circuit status Normal
Off
ALM LED
'Output short-circuit
0
detection status' (Un\G3088)
'Alarm flag'
(X11)
OFF
'Alarm clear request'
(Y11)
OFF
: Performed by the output module with diagnostic functions.
: Performed by a program.
Valve C
Short circuit
or ground fault
Valve D
Short circuit
On
1
ON
Normal
Off
0
ON
1 FUNCTIONS
49
1.4 Diagnostic Function
1