Yaskawa Matrix Converter - Manual (Page 332)

Protective and Diagnostic Functions
7-
11
‹ Alarm Detection
Alarms are detected as a type of MxC protection function that do not operate the fault contact output. The sys-
tem will automatically returned to its original status once the cause of the alarm has been removed.
The digital operator display flashes and the alarm is output from the multi-function outputs (H2-01 to H2-03).
When an alarm occurs, take appropriate countermeasures according to the table below.
Table 7.2 Alarm Displays and Processing
Display Meaning Probable causes Corrective Actions
EF
(flashing)
External
Fault
Forward/Reverse Run Commands
Input Together
Both the Forward and Reverse Run
Commands have been on for more
than 0.5 s.
-
Check the sequence of the Forward
and Reverse Run Commands.
The motor will stop by the stopping
method that is set in b1-03 when this
fault occurs.
UV
(flashing)
PS Und-
ervolt
Control Circuit Undervoltage
The following conditions occurred
when there was no run signal.
• The control circuit voltage was
below the Undervoltage Detection
Level Setting (L2-05).
• The control power supply voltage
was below the CUV level.
See causes for UV1 and UV2 faults in
the previous table. See corrective actions for UV1 and
UV2 faults in the previous table.
AUV
(flashing)
Power
UV
Power Supply Undervoltage
The power supply is below the under-
voltage detection level (L2-21).
200 V class: Approx. 150 VAC
400 V class: Approx. 300 VAC
• The power voltage is too high.
• The power capacity is too small.
• The power distortion is too large.
• Decrease the voltage to be within
specifications.
• Increase the power capacity.
• Decrease the impedance of the input
power wiring.
For details, refer to MxC Application
Precautions in Chapter 10.
An open phase occurred in the input
power supply.
Check and correct the open-phase con-
dition or the imbalance of the input
power.
Clear the fault after correcting the
problem or removing its cause.
Check if a short circuit occurred
between the following terminals.
R/L1 ← → r2,
S/L2 ← → s2,
T/L3 ← → t2
Replace the MxC.
FDV
(flashing)
Freq
DEV
Power Supply Frequency Fault
The fluctuation in the power fre-
quency exceeded the allowable
amount.
• A momentary power loss occurred.
• The wiring terminals for the input
power supply are loose.
• The voltage fluctuations in the
input power supply are too large.
• The voltage balance between
phases is not equal.
• Increase the power capacity.
• Decrease the impedance of the input
power wiring.
Clear the fault after correcting the
problem or removing its cause.
For details, refer to MxC Application
Precautions in Chapter 10.
Power Supply Undervoltage
The power supply is below the under-
voltage detection level (L2-21).
200 V class: Approx. 150 VAC
400 V class: Approx. 300 VAC
• A momentary power loss occurred.
• The wiring terminals for the input
power supply are loose.
• The voltage fluctuations in the
input power supply are too large.
• The voltage balance between
phases is not equal.
• Increase the power capacity.
• Decrease the impedance of the input
power wiring.
Clear the fault after correcting the
problem or removing its cause.
For details, refer to MxC Application
Precautions in Chapter 10.