Digital Operator Display
Minor Fault Name
LT-3
Soft Charge Bypass Relay Maintenance Time
The DC bus soft charge relay is nearing the end of its expected performance life.
Note:
The signal closes when the maintenance period ends if H2-
oo
= 2F. The signal will not close
if H2-
oo
= 10.
Cause
Possible Solutions
The DC bus soft charge relay has reached
90% of expected performance life.
Replace the drive.
Digital Operator Display
Minor Fault Name
LT-4
IGBT Maintenance Time (50%)
IGBTs have reached 50% of their expected performance life.
Note:
The signal closes when the maintenance period ends if H2-
oo
= 2F. The signal will not close
if H2-
oo
= 10.
Cause
Possible Solutions
IGBTs have reached 50% of their expected
performance life.
Check the load, carrier frequency, and output frequency.
Digital Operator Display
Minor Fault Name
oH
Heatsink Overheat
The temperature of the heatsink exceeded the overheat pre-alarm level set to L8-02 (90-100 °C). Default
value for L8-02 is determined by drive capacity (o2-04).
Cause
Possible Solutions
Surrounding temperature is too high
• Check the surrounding temperature.
• Improve the air circulation within the enclosure panel.
• Install a fan or air conditioner to cool surrounding area.
• Remove anything near drive that may cause extra heat.
Internal cooling fan has stopped.
• Replace the cooling fan.
• After replacing the drive, set parameter o4-03 to 0 to reset the cooling fan operation time.
Airflow around the drive is restricted.
• Provide proper installation space around the drive.
• Allow for the proper space and ensure that there is sufficient circulation around the control panel.
• Check for dust or other foreign materials clogging the cooling fan.
• Clear debris caught in the fan that restricts air circulation.
Digital Operator Display
Minor Fault Name
oH2
Heatsink Overheat Warning
“Heatsink Overheat Warning” was input to a multi-function input terminal, S1 through S8 (H1-
oo
= B).
Cause
Possible Solutions
An external device triggered an overheat
warning in the drive.
Search for the device that tripped the overheat warning. Remove the cause of the problem.
Digital Operator Display
Minor Fault Name
oH3
Motor Overheat
The motor overheat signal entered to a multi-function analog input terminal exceeded the alarm level (H3-02,
H3-06 or H3-10 = E).
Cause
Possible Solutions
Motor thermostat wiring is faulty (PTC
input).
Repair the PTC input wiring.
There is a fault on the machine side (e.g.,
the machine is locked up).
• Check the status of the machine.
• Remove the cause of the fault.
2.5 Alarm Detection
208
YASKAWA ELECTRIC SIEP YEAHHP 01B YASKAWA AC Drive – A1000 HHP Programming Manual
Summary of Contents for A1000 HHP
Page 359: ......
