YASKAWA L1000A Technical Manual page 303

Digital Operator Display
ov
Cause
Surge voltage present in the drive input power.
The motor is short-circuited.
Ground current has over-charged the main circuit
capacitors via the drive input power.
Noise interference causes the drive to operate
incorrectly.
Encoder cable is disconnected.
Encoder cable wiring is wrong.
Noise interference along encoder wiring.
Digital Operator Display
PASS
Cause
MEMOBUS/Modbus test has finished normally.
Digital Operator Display
PGo
Cause
Encoder cable is disconnected.
Encoder cable wiring is wrong.
Encoder does not have enough power.
Motor brake is not released.
Digital Operator Display
PGoH
Cause
Encoder cable is disconnected.
Digital Operator Display
SE
Cause
A digital input set to 67H (MEMOBUS/Modbus
test) was closed while the drive was running.
Digital Operator Display
TrPC
Cause
IGBTs have reached 90% of their expected
performance life.
Digital Operator Display
UL3
Cause
Inappropriate parameter settings.
Load has dropped or decreased significantly.
Digital Operator Display
UL4
Cause
Inappropriate parameter settings.
The load has dropped or decreased significantly.
YASKAWA ELECTRIC SIEP C710616 38F YASKAWA AC Drive - L1000A Technical Manual
DC Bus Overvoltage
The DC bus voltage exceeded the trip point.
For 200 V class: approximately 410 V
For 400 V class: approximately 820 V
For 600 V class drives: approximately 1040 V
• Install a DC link choke or an AC reactor.
• Voltage surge can result from a thyristor convertor and a phase advancing capacitor operating on the same drive input power
system.
• Check the motor power cable, relay terminals and motor terminal box for short circuits.
• Correct grounding shorts and turn the power back on.
• Review possible solutions for handling noise interference.
• Review section on handling noise interference and check control circuit lines, main circuit lines and ground wiring.
• If the magnetic contactor is identified as a source of noise, install a surge protector to the MC coil.
Set number of fault reset (L5-01) to a value other than 0.
Reconnect the cable.
Correct the wiring.
Separate encoder wiring from the source of the noise (often output wiring from the drive).
MEMOBUS/Modbus Communication Test Mode Complete
This verifies that the test was successful.
Encoder Disconnected (for Control Mode with Encoder)
Detected when no encoder signal is received for a time longer than setting in F1-14.
Reconnect the cable.
Correct the wiring.
Make sure the correct power supply is properly connected to the encoder.
Ensure the brake releases properly
Encoder Disconnected (detected when using an encoder)
Encoder cable has become disconnected.
Reconnect the cable.
MEMOBUS/Modbus Self Test Failed
Stop the drive and run the test again.
IGBT Maintenance Time (90%)
IGBTs have reached 90% of their expected performance life.
Note: This alarm will not trigger a multi-function output terminal that is set for alarm output (H2- = 10).
Replace the drive.
Undertorque Detection 1
Drive output current (or torque in OLV, CLV, CLV/PM) less than L6-02 for longer than L6-03 time.
Check parameters L6-02 and L6-03.
Check for broken parts in the transmission system.
Undertorque Detection 2
Drive output current (or torque in OLV, CLV, CLV/PM) less than L6-05 for longer than L6-06 time.
Check parameters L6-05 and L6-06.
Check for broken parts in the transmission system.
6.4 Alarm Detection
Minor Fault Name
Possible Solutions
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Possible Solutions
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions
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