User Manual

Chapter 9 Error Codes
9 - 3
9.2 Error Codes and Troubleshooting
It is not displayed with the standard panel.
Name Description
Display on digital
operator
Troubleshooting and corrective action
Reference
page
Overcurrent
protection
If the motor is constrained or
suddenly accelerated or
decelerated, a high current will
flow in the inverter and the
inverter may fail. To avoid this
problem, the inverter shuts off its
output and displays the error
code shown on the right when it
detects a current higher than a
specified level.
This protective function uses a
DC current detector (CT) to
detect overcurrent.
When a current as high as about
235%(peak) of the inverter's rated
output current is detected, the
protective circuit operates and the
inverter trips. (*4)
During
constant-
speed
operation
Check whether the load has fluctuated sharply.
(Eliminate the load fluctuation.)
Check for the short circuit of output connections.
(Check the output cables.)
Check for the ground fault.
(Check the output cables and motor.)
7-8
7-22
During
deceleration
Check whether the inverter has decelerated the motor
quickly.
(Increase the deceleration time.)
During
acceleration
Check whether the inverter has accelerated the motor
quickly.
(Increase the acceleration time.)
Check whether the motor has been locked.
(Check the motor and wiring.)
Check whether the torque boost current has been set
too high.
(Reduce the boost current.)
Others
Check whether the DC braking force is too high.
(Reduce the braking force.)
Check whether the current detector (CT) is normal.
(Replace or repair the CT.)
7-41
Overload
protection
(*1)
This protective function monitors the inverter
output current, and shuts off the inverter output
and displays the error code shown on the right
when the internal electronic thermal protection
circuit detects a motor overload.
If the error occurs, the inverter will trip according
to the setting of the electronic thermal function.
Check whether the motor load is too high.
(Reduce the load factor.)
Check whether the thermal level is appropriate.
(Adjust the level appropriately.)
Note:
The electronic thermal protection is easily triggered
when the output frequency is 5 Hz or less. If the
moment of inertia of the load is large, this protective
function may operate when the inverter accelerates
the motor and the acceleration may be disabled. If this
problem occurs, increase the torque boost current or
adjust other settings as needed.
7-61
7-63
Overvoltage
protection
If the DC voltage across the P and N terminals
rises too high, an inverter failure may result. To
avoid this problem, this protective function shuts
off the inverter output and displays the error code
shown on the right when the DC voltage across
the P and N terminals exceeds a specified level
because of an increase in the energy regenerated
by the motor or the input voltage (during
operation).
The inverter will trip if the DC voltage across the P
and N terminals exceeds about 400 VDC (in case
of the 200 V class models) or about 800 VDC (in
case of the 400 V class models).
Check whether the inverter has decreased the motor
quickly.
(Increase the deceleration time.)
Check for a ground fault.
(Check the output cables and motor.)
Check whether the motor has been rotated by the
action of the load.
(Reduce the regenerative energy.)
7-8
Memory
error
(*2) (*3)
When the built-in Memory is caused by external
noise or an abnormal temperature rise, the
inverter shuts off its output and displays the error
code shown on the right.
Note: A Memory error may cause a CPU error.
Check for the noise sources located near the inverter.
(Remove noise sources.)
Check whether the cooling efficiency has deteriorated.
(Check the heat sink for clogging, and clean it.)
(Replace the cooling fan.)
-
Under
voltage
If the inverter input voltage drops, the control
circuit of the inverter cannot function normally.
Therefore, the inverter shuts off its output when
the input voltage falls below a specified level.
The inverter will trip if the DC voltage across the P
and N terminals exceeds about 175 VDC (in case
of the 200 V class models) or about 345 VDC (in
case of the 400 V class models).
Check whether the power supply voltage has
dropped.
(Check the power supply.)
Check whether the power supply capacity is sufficient.
(Check the power supply.)
-
Current
detection
error
If an error occurs in the internal current detector
(CT), the inverter will shut off its output and
display the error code shown on the right.
Check whether the inverter has failed.
(Repair the inverter.)
-
CPU error
(*3)
If the internal CPU malfunctions or an error occurs
in it, the inverter will shut off its output and display
the error code shown on the right.
Note: Reading an abnormal data from the built-in
memory may result in a CPU error.
Check for the noise sources located near the inverter.
(Remove noise sources.)
Check whether the inverter has failed.
(Repair the inverter.)
-
*1 The inverter will not accept any reset command within about 10 seconds after tripping (i.e., after the protective function operates).
*2 The inverter will not accept any reset command after a Memory error occurs with error code displayed. Turn off the
inverter power once. If error code "E08" is displayed when the inverter power is turned on subsequently, the internal memory
device may have failed or parameters may have not been stored correctly. In such cases, initialize the inverter, and then re-set the
parameters.
*3 The inverter will not accept reset commands input via the RS terminal or entered by the STOP/RESET key. Therefore, turn off the
inverter power.
*4 At the time of trip occurrence, as for the effective-value electric current with the measuring instrument and the current value of the
trip history, a low value may be displayed by timing of the data sampling.