Cause
Possible Solutions
Minor Fault
Output
(H2-01 = 10)
A digital input programmed to
67H (MEMOBUS/Modbus
test) was closed while the drive
was running.
Stop the drive and run the test again.
No output
LED Operator Display
Minor Fault Name
Uv
Undervoltage
One of the following conditions occurred while the drive was in operation:
• DC bus voltage dropped below the under voltage detection level.
• Contactor to suppress inrush current in the drive was open.
• Low voltage in the control drive input power. This alarm outputs only if L2-01 is
not 0 and DC bus voltage is below the detection level.
Cause
Possible Solutions
Minor Fault
Output
(H2-01 = 10)
Phase loss in the drive input
power.
Check for wiring errors in the main circuit drive input power.
Correct the wiring.
YES
Loose wiring in the drive input
power terminals.
• Ensure the terminals have been properly tightened.
• Apply the tightening torque specified in this manual to fasten
Refer to Wire Gauges and Tightening
YES
There is a problem with the
drive input power voltage.
• Check the voltage.
• Lower the voltage of the drive input power so that it is within
the limits listed in the specifications.
YES
Drive internal circuitry is
worn.
• Check the maintenance time for the capacitors (U4-05).
• Replace the drive if U4-05 exceeds 90%.
YES
The drive input power
transformer is not large enough
and voltage drops when the
power is switched on.
• Check for a tripped alarm when the magnetic contactor, line
breaker and leakage breaker are turned on.
• Check the capacity of the drive input power transformer.
YES
Air inside the drive is too hot. • Check the temperature inside the drive.
YES
The CHARGE indicator light
is broken or disconnected.
• Replace the drive.
YES
5.5 Alarm Detection
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5
Troubleshooting
