YASKAWA Z1000 User Manual page 221

Digital Operator Display
LT-3
Cause
The DC bus soft charge relay has reached
90% of expected performance life.
Digital Operator Display
LT-4
Cause
IGBTs have reached 50% of their expected
performance life.
Digital Operator Display
Cause
Surrounding temperature is too high
Internal cooling fan has stopped.
Airflow around the drive is restricted.
YASKAWA TOEP YAIZ1U 03B YASKAWA AC Drive – Z1000 User Manual
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.
Replace the drive.
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.
Check the load, carrier frequency, and output frequency.
Heatsink Overheat
oH
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 model selection (o2-04).
• 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.
• Replace the cooling fan.
• After replacing the drive, set parameter o4-03 to 0 to reset the cooling fan operation time.
• Provide proper installation space around the drive as indicated in the manual.
Orientation and Spacing on page 38
• 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.
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions
for details.
5.5 Alarm Detection
Refer to Installation
221
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