Operation selection at power failure
If offline auto tuning ended in error (see the table below), motor constants are not set. Perform
an inverter reset and restart tuning.
Tab. 6-44: Value of Parameter 96
When tuning is ended forcibly by pressing the STOP-key or turning off the start signal (STF or
STR) during tuning, offline auto tuning does not end normally. (The motor constants have not
been set.) Perform an inverter reset and restart tuning.
When using the motor corresponding to the following specifications and conditions, reset Pr.9
Electronic thermal O/L relay as below after tuning is completed.
● When the rated power specifications of the motor is 200/220V(400/440V) 60Hz, set 1.1 times
rated motor current value in Pr. 9.
● When performing motor protection from overheat using a PTC thermistor or motor with
temperature detector such as Klixon, set "0" (motor overheat protection by the inverter is
invalid) in Pr. 9.
The motor constants measured once in the offline auto tuning are stored as parameters and
their data are held until the offline auto tuning is performed again.
An instantaneous power failure occurring during tuning will result in a tuning error. After
power is restored, the inverter goes into the normal operation mode. Therefore, when STF
(STR) signal is on, the motor runs in the forward (reverse) rotation.
Any alarm occurring during tuning is handled as in the ordinary mode. Note that if an error
retry has been set, retry is ignored.
The set frequency monitor displayed during the offline auto tuning is 0Hz.
Changing the terminal assignment using Pr. 178 to Pr. 184 "Input terminal function selec-
tion" may affect the other functions. Make setting after confirming the function of each termi-
The SU and FU signals are not output during a restart. They are output after the restart
cushion time has elapsed.
Automatic restart operation will also be performed after a reset or when a retry is made by
the retry function.
6 - 160
Inverter protective function operation
Current limit (stall prevention) function was
Converter output voltage reached 75% of
– Calculation error
– A motor is not connected.
Set "21" in Pr. 96 and perform tuning again.
Make setting again.
Set "1" in Pr. 156.
Check for fluctuation of power supply voltage.
Check the motor wiring and make setting
Set the rated current of the motor in Pr. 9.