Instruction manual

8. Fault Diagnosis
175
 Troubleshooting
Trouble Cause Corrective Actions
The motor does not
operate when an
external operation
signal is input.
The operation method selection
is wrong.
The RUN command (n003) is not set
to Control Circuit Terminal.
Set the RUN command (n003) to
Control Circuit Terminal.
A 3-wire sequence is in effect.
The Multi-function Input Selection
(n052) is set to 3-wire sequence, and
the S2 control terminal is not closed.
To use a 3-wire sequence, make the
wiring so that the S2 control terminal
is closed. To use a 2-wire sequence,
set the Multi-function Input (n052) to a
value other than 3-wire sequence.
The frequency reference is too
low.
The input frequency reference is lower
than the setting for the Min.Output
Frequency (n016).
Input a frequency reference greater
than the Min. Output Frequency
(n016).
Local mode is in effect.
Set the LO/RE selection of the Digital
Operator to RE.
The V-I SW (SW2) setting is
wrong.
Example: The reference 4-20 mA is in-
put, but the SW2 is set to “V.”
For analog input, make sure that the
Frequency Reference (n004) and SW2
settings are correct.
The setting of NPN/PNP switch
(SW1) is not correct.
Set SW1 correctly.
The motor stops. The
torque is not output.
The stall prevention level during
acceleration is too low.
Because the Stall Prevention Level
during Acceleration (n093) is set too
low, the output current reaches the set
level, the output frequency is stopped,
and the acceleration time is
lengthened.
Check if the Stall Prevention Level
during Acceleration (n093) is set to an
appropriate value.
The stall prevention level during
running is too low.
Because the Stall Prevention Level
during Running (n094) is set too low,
the output current reaches the set
level, and the speed drops.
Check if the Stall Prevention Level
during Running (n094) is set to an
appropriate value.
The load is too heavy.
If the load is too heavy, stall prevention
is activated, the output frequency is
stopped, and the acceleration time is
lengthened.
• Lengthen the set acceleration time
(n019).
• Reduce the load.
When the maximum frequency
was changed, the maximum
voltage frequency was also
changed.
To increase the speed of a general-
purpose motor, only change the
maximum frequency.
The V/f set value is too low.
Set the V/f (n011 to n017) according to
the load characteristics.