Mitsubishi Electric A800 Programming Manual page 35

Special registers to monitor and control inverter status
Fault clear signal (X51 signal)
When an inverter fault occurs, X51 signal clears the fault without resetting the inverter.
By using the X51 signal, the inverter fault can be cleared with the PLC function still operating.
Set "51" in Pr.178 to Pr.189 (Input terminal function selection) in advance to enable the X51 signal.
Fault status
(terminal ABC)
X51 signal
• The fault clear function using the X51 signal does not function while the retry function is operating (including during the retry
waiting time).
(The X51 signal operates when the retry count is exceeded (E.RET).
• When the fault is cleared, start commands from PU and communication are also cleared. (All commands except the start
command from communication are maintained in the status before the fault is cleared.)
NOTE
• E.CPU, E.P24, E.CTE, E.1 to E.3, E.5 to E.7, E.13, E.16 to E.20, E.SAF and E.PE2 are not cleared by X51 signal.
• When a fault is cleared, the accumulated heat values of the electronic thermal O/L relay and regenerative brake are not
cleared. Faults including E.THM, E.THT, and E.BE may occur again.
• The inverter remains in the stop status immediately after a fault is cleared. However, the inverter starts operating again after
the fault is cleared if the start command is ON.
• When an error occurs, the normal reset function operates when the STOP/RESET key on the operation panel or parameter
unit is pushed. Be careful not to push the key by mistake.
• Changing terminal assignment by using Pr.178 to Pr.189 (input terminal function selection) may affect the other functions.
Set parameters after confirming the function of each terminal.
34
PLC Function
Fault occurs
OFF ON OFF
Fault is cleared by turn
ON of X51 signal.
If a fault occurs while the X51 signal has
been ON, the fault is not cleared.
ON OFF
If a fault occurs while the X51
signal has been ON, turn OFF
the X51 signal once, then turn it
ON again.
ON
Fault is cleared by
turn ON of X51 signal.