Mitsubishi Electronics A800 Welding System User Manual


 
Inverter fault and alarm indications
80
PROTECTIVE FUNCTIONS
4.1 Inverter fault and alarm indications
When the inverter detects a fault, depending on the nature of the fault, the operation panel displays an error message or
warning, or a protective function activates to trip the inverter.
When any fault occurs, take an appropriate corrective action, then reset the inverter, and resume the operation. Restarting
the operation without a reset may break or damage the inverter.
When a protective function activates, note the following points.
Inverter fault or alarm indications are categorized as below.
NOTE
For the details of fault displays and other malfunctions, refer to the FR-A800 Instruction Manual (Detailed).
The past eight faults can be displayed on the operation panel. (Faults history) (For the operation, refer to page 81.)
4.2 Reset method for the protective functions
Reset the inverter by performing any of the following operations. Note that the accumulated heat value of the electronic
thermal relay function and the number of retries are cleared (erased) by resetting the inverter.
The inverter recovers about 1 s after the reset is released.
NOTE
OFF status of the start signal must be confirmed before resetting the inverter fault. Resetting an inverter fault with the start
signal ON restarts the motor suddenly.
Item Description
Fault output signal
Opening the magnetic contactor (MC) provided on the input side of the inverter at a fault occurrence
shuts off the control power to the inverter, therefore, the fault output will not be retained.
Fault or alarm indication When a protective function activates, the operation panel displays a fault indication.
Operation restart method
While a protective function is activated, the inverter output is kept shutoff. Reset the inverter to restart
the operation.
Displayed item Description
Error message
A message regarding an operational fault and setting fault by the operation panel (FR-DU08) and
parameter unit (FR-PU07) is displayed. The inverter does not trip.
Warning
The inverter does not trip even when a warning is displayed. However, failure to take appropriate
measures will lead to a fault.
Alarm The inverter does not trip. An Alarm (LF) signal can also be output with a parameter setting.
Fault A protective function activates to trip the inverter and output a Fault (ALM) signal.
On the operation panel, press to reset the inverter.
(This may only be performed when a fault occurs.)
Switch power OFF once, then switch it ON again.
Turn ON the reset signal (RES) for 0.1 s or more. (If the RES signal
is kept ON, "Err" appears (flickers) to indicate that the inverter is in
a reset status.)
ON
OFF
SD
Inverter
RES