Hitachi J300U Series - Manual (Page 81)

9-8
Symptom Probable cause Countermeasure
Overload
(Electronic
thermal
trip)
(Low
frequency
zone) Is the torque boost too high ?
Do the electronic thermal characteristics
match the set characteristics of the
motor ? Decrease the torque boost.
Reset the electronic thermal characteristics
and level.
Is the input voltage high ?
Is the equipment stopped with the
inverter DC voltage increased after
sudden deceleration ? Lower the input voltage.
Set a deceleration time which is a little longer.
Increase the AVR set value above the current
input voltage and lower the V gain by
the ratio. The input
voltage
trips.