Mitsubishi Electric 800 Series Instruction Manual page 432

NOTE
• 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. However, the tuning data is cleared by performing all parameter clear.
• Changing Pr.71 (Pr.450) after tuning completion will change the motor constant. For example, if Pr.71 = "3" is set after tuning
is performed with Pr.71 = "0", the tuning data becomes invalid. Set Pr.71 = "0" again for using the tuning data.
• If offline auto tuning has ended in error (see the table below), motor constants are not set. Perform an inverter reset and
restart tuning.
Error display
8 Forced end
9 Inverter protective function operation
The current limit (stall prevention) function is
91
activated.
The converter output voltage has dropped to
92
75% of the rated voltage.
Calculation error
93
The motor is not connected.
Rotation tuning frequency setting error
(The frequency command for the tuning was
94
given to exceed the maximum frequency
setting, or to be in the frequency jump range.)
• When tuning is ended forcibly by pressing
tuning does not end properly. (The motor constants have not been set.)
Perform an inverter reset and restart tuning.
NOTE
• An instantaneous power failure occurring during tuning will result in a tuning error. After power is restored, the inverter starts
normal operation. 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 normal operation. Note that even if a retry operation has been set,
retry is not performed.
• The set frequency monitor displayed during the offline auto tuning is 0 Hz
CAUTION
 Note that the motor may start running suddenly.
 For the offline auto tuning in vertical lift applications, etc., caution is required to avoid falling due to
insufficient torque.
Error cause
or turning OFF the start signal (STF or STR) during tuning, offline auto
(C) Motor constant parameters
Countermeasures
Set Pr.96 = "1" or "101" and try again.
Make the setting again.
Set the acceleration/deceleration time longer.
Set Pr.156 = "1".
Check for the power supply voltage fluctuation.
Check the Pr.83 Rated motor voltage setting.
Check the Pr.83 and Pr.84 settings.
Check the motor wiring and make the setting again.
Check the Pr.1 Maximum frequency and Pr.31 to
Pr.36 Frequency jump settings.
PARAMETERS
5
GROUP
C
431