Hitachi SJ Series User Manual page 614

Chapter 18
E039 Controller (inverter)
overload error
The built-in electronic thermal function monitors the
output current of the inverter (controller) and when
inverter overload is detected, the inverter turns
OFF its output.
Occurrence Estimated cause(s)
• Operation under heavy
Error occurred after
a fixed period of load condition has
operation. continued.
• Insufficient acceleration
torque
• Load inertia is large.
Error occurred
• Friction torque is large.
during
acceleration.
• A function to suppress
overcurrent is at work.
• Load inertia is large.
Error occurred
during
deceleration.
• A function to suppress
overvoltage is at work.
• System environment
changes
Error occurred
after long hours of
use.
• Aging deterioration
Exemplar measures to be taken
• Re-examination of operation condition or correction of load condition
may improve the situation.
• Setting longer acceleration time in [FA-10] can ease the insufficient
acceleration torque.
• When acceleration torque is required, the situation may be
improved by adjusting the boost function in [Hb141], or by
operating the inverter and making adjustments with control method
in [AA121].
• Re-examination of load condition may improve the situation.
• A factor for overcurrent may have been occurred. Re-examination of
acceleration time or load condition is required.
• Insufficient rotation regeneration torque can be eased by setting
longer deceleration time in [FA-12].
• When regenerative torque is required, the situation may be
improved by adjusting the boost function in [Hb141], or by
operating the inverter and adjusting with control method in [AA121].
• Re-examination of load condition may improve the situation.
• Current may increase as a result of suppressing overvoltage.
Re-examination of deceleration time or load condition is required.
• The situation may be improved by reducing the motor load, or
performing a system maintenance (e.g., cleaning the fan to be
driven and removing clogging in the duct).
• If the issue is not solved by reduction of the load and system
maintenance, aging deterioration of a life-limited component may be
the cause. A repair is required.
18-21
Tips/FAQ/Troubleshooting
E039