YASKAWA A1000 HHP - Page 211

Digital Operator Display Minor Fault Name
SE
MEMOBUS/Modbus Communication Test Mode Error
Note: This alarm will not trigger a multi-function output terminal that is set for alarm output
(H2-oo = 10).
Cause Possible Solutions
A digital input set to 67H (MEMOBUS/
Modbus test) was closed while the drive
was running.
Stop the drive and run the test again.
Digital Operator Display Minor Fault Name
THo
Thermistor Disconnect
The thermistor used to detect motor temperature has become disconnected.
Cause Possible Solutions
The motor thermistor is not connected
properly.
Check the thermistor wiring.
Digital Operator Display Minor Fault Name
TrPC
IGBT Maintenance Time (90%)
IGBTs have reached 90% of their expected performance life.
Cause Possible Solutions
IGBTs have reached 90% of their expected
performance life.
Replace the drive.
Digital Operator Display Minor Fault Name
UL3
Undertorque Detection 1
Drive output current (or torque in OLV, CLV, AOLV/PM, and CLV/PM) less than L6-02 for longer than
L6-03 time.
Cause Possible Solutions
Inappropriate parameter settings. Check parameters L6-02 and L6-03.
Load has dropped or decreased
significantly.
Check for broken parts in the transmission system.
Digital Operator Display Minor Fault Name
UL4
Undertorque Detection 2
Drive output current (or torque in OLV, CLV, AOLV/PM, and CLV/PM) less than L6-05 for longer than
L6-06 time.
Cause Possible Solutions
Inappropriate parameter settings. Check parameters L6-05 and L6-06.
The load has dropped or decreased
significantly.
Check for broken parts in the transmission system.
Digital Operator Display Minor Fault Name
Uv
Undervoltage
One of the following conditions was true when the drive was stopped and a Run command was entered:
• DC bus voltage dropped below the level specified in L2-05.
• Contactor to suppress inrush current in the drive was opened.
• Low voltage in the control drive input power. This alarm outputs only if L2-01 is not 0 and DC bus voltage
is under L2-05.
Cause Possible Solutions
Phase loss in the drive input power. Check for wiring errors in the main circuit drive input power. Correct the wiring.
Loose wiring in the drive input power
terminals.
• Check for loose terminals.
• Ensure the terminals have been properly tightened.
• Apply the tightening torque to the terminals.
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.
2.5 Alarm Detection
YASKAWA ELECTRIC SIEP YEAHHP 01B YASKAWA AC Drive – A1000 HHP Programming Manual
211
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Troubleshooting