Yaskawa AC Drive-P1000 Industrial Fan User Manual
Page 310
Cause
Possible Solution
In drive models 2A0004 to 2A0056 or 4A0002
to 4A0031, L2-02 was changed from its
default value without installing a Momentary
Power Loss Ride-Thru unit
Correct the setting to L2-02 or install an optional Momentary Power Loss Ride-Thru unit.
Control power supply wiring is damaged
• Cycle power to the drive. Check if the fault reoccurs.
• If the problem continues, replace the control board, the entire drive, or the control power supply. For
instructions on replacing the control board, contact Yaskawa or a Yaskawa representative.
Internal circuitry is damaged
• Cycle power to the drive. Check if the fault reoccurs.
• If the problem continues, replace either the control board or the entire drive. For instructions on
replacing the control board, contact Yaskawa or a Yaskawa representative.
Digital Operator Display
Fault Name
Uv3
Undervoltage 3 (Soft-Charge Bypass Relay Fault)
The soft-charge bypass relay failed.
Cause
Possible Solution
The relay or contactor on the soft-charge
bypass relay is damaged
• Cycle power to the drive and see if the fault reoccurs.
• Check monitor U4-06 for the performance life of the soft-charge bypass relay.
• Replace either the control board or the entire drive if U4-06 exceeds 90%. For instructions on replacing
the control board, contact Yaskawa or a Yaskawa representative.
Digital Operator Display
Fault Name
<1>
Uv4
Gate Drive Board Undervoltage
Voltage drop in the gate drive board circuit
Cause
Possible Solution
Not enough power is being supplied to the gate
drive board.
• Cycle power to the drive and see if the fault reoccurs.
Refer to Diagnosing and Resetting Faults on
for details.
• If the problem continues, replace either the gate drive board or the entire drive. For instructions on
replacing the gate drive board, contact Yaskawa or a Yaskawa representative.
<1> Detected in models 4A0930 and 4A1200.
Digital Operator Display
Fault Name
voF
Output Voltage Detection Fault
Problem detected with the voltage on the output side of the drive.
Cause
Possible Solution
Hardware is damaged. Internal drive module
MC / FAN overheat protection circuit board is
due to abnormal ambient operating power.
• Lower ambient temperature.
• Replace the control board or the entire drive. For instructions on replacing the control board, contact
Yaskawa or a Yaskawa representative.
Digital Operator Display
Fault Name
vToL
VT Overload
Cause
Possible Solution
The output current of the drive has been
elevated for a set length of time.
The application may not be suited for the drive
• The application may not be suited for the drive
• The drive is undersized for the load
6.4 Fault Detection
310
YASKAWA SIEP YAIP1U 01B AC Drive - P1000 Technical Manual