Hitachi NES1-002LB, Quick Reference Manual

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Chapter 10 Troubleshooting
10 - 3
10. .Overcurrent trip (E03)
Possible Cause(s) Corrective Action
Acceleration time is short. Change acceleration time (F002/A092/A292).
Enable "acceleration hold" function (A069,A070)
Excess load. Remove excess load.
Enable torque boost function.
Set free V/f in V/F characteristic curve selection (A044/A244=02)
Overload restriction (b021) is disabled (00). Enable overload restriction (b021=01/02).
When the inverter trips due to Overcurrent(E03), despite overload restriction is enabled(b021=01/02).
Overload restriction level (b022/b025) is
high. Set overload restriction level (b022/b025) lower.
Deceleration rate at overload restriction
(b023/b026) is too short. Set deceleration rate at overload restriction (b023/b026) longer.
11. STOP/RESET key does not respond.
Possible Cause(s) Corrective Action
STOP/RESET key disabled. Check "STOP key enable" function. (b087)
Deceleration overvoltage suppression
(b130) or controlled deceleration on power
loss (b050) function is enabled. Check b130 and b050.
12. Sound noise of motor or machine.
Possible Cause(s) Corrective Action
Carrier frequency is low. Set carrier frequency (b083) higher. (This could cause electric noise
and leak current higher.)
Machine frequency and motor frequency
are resonated. Change output frequency slightly. If resonating in accel/deceleration,
use jump frequency function (A063-68) to avoid machine frequency.
Over excitation Set base frequency (A003/A203) and AVR voltage (A082/A282)
according to motor rating. If not improved, reduce V/f gain
(A045/A245) slightly or change V/f curve (A044/A244) as free V/f.
13. Overload trip (E05).
Possible Cause(s) Corrective Action
Improper electronic thermal level Check electronic thermal setting (b012/b013)
14. Over voltage trip (E07).
Possible Cause(s) Corrective Action
Short deceleration time Change deceleration time. (F003/F203/A093/A293)
Overvoltage suppression during
deceleration (b130) is disabled (00). Enable overvoltage suppression (b130=01/02).
When the inverter trips due to over voltage, despite over voltage suppression is enabled.
Improper overvoltage suppression
propotional gain (b134) or integral time
(135). Check overvoltage suppression proportional gain (b134) and integral
time (b135).
Overvoltage suppression level (b131) is
high. Set Overvoltage suppression level (b131) lower. (Lower limit of
parameter b131 must be (input voltage)
×√
2
×
1.1.)
15. Unstable output frequency.
Possible Cause(s) Corrective Action
Improper parameters Set output frequency slightly smaller or bigger value than power
source frequency.
Change motor stabilization constant (H006/H206).
Reduce carrier frequency (b083).
Reduce V-Gain (A045).
Load variation is excessive. Change motor and inverter to one size bigger.
Power voltage variation is excessive. Check power source.