Yaskawa Varispeed-656 DC5 - Manual (Page 55)

6 TROUBLESHOOTING
E-45
6.2 Minor Fault Detection
Minor faults are a type of VS-656DC5 protection function that do not operate the fault con-
tact output and are automatically returned to their original status once the cause of the minor
fault has been removed.
The Digital Operator display blinks and the minor fault is output from the multi-function
outputs.
Take appropriate countermeasures according to the table below.
Table 13 Minor Fault Displays and Troubleshooting
Minor Fault Display Meaning Probable Causes Corrective Actions
UV (blinking)
DC Bus Undervolt
Main Circuit Undervoltage
The following conditions occurred when
there was no Run signal.
• The main circuit DC voltage was
below the main circuit DC voltage
detection level (L2-05).
• The inrush current limiting contactor
opened.
• The control power supply voltage
when below the undervoltage (input
voltage low level).
• Frequency detection exceeded the
allowable level.
• Voltage phase rotation at the input side
changed.
Refer to probable causes for
UV1, UV2, UV3, FdEv, and
SrC faults. Refer to probable corrective
actions for UV1, UV2, UV3,
FdEv, and SrC faults.
OV (blinking)
DC Bus Overvolt
Main Circuit Overvoltage
The main circuit DC voltage exceeded
the overvoltage detection level.
200 V class: Approx. 400 VDC or more
400 V class: Approx. 800 VDC or more
The power supply voltage is
too high. Decrease the voltage so it's
within specifications.
OH (blinking)
Heatsnk Over temp
Cooling Fin Overheating
The temperature of the VS-656DC5
cooling fins exceeded the setting in L8-
02.
The ambient temperature is too
high. Install a cooling unit.
There is a heat source nearby. Remove the heat source.
The VS-656DC5 cooling fan
has stopped. Replace the cooling fan. (Contact
your Yaskawa representative.)
EF3 (blinking)
External Fault 3
External fault (Input terminal 3) An “External fault” was input
from a multi-function input. • Reset external fault inputs to
the multi-function inputs.
• Remove the cause of the exter-
nal fault.
EF4 (blinking) External fault (Input terminal 4)
EF5 (blinking) External fault (Input terminal 5)
EF6 (blinking) External fault (Input terminal 6)
EF7 (blinking) External fault (Input terminal 7)
EF8 (blinking) External fault (Input terminal 8)