Mitsubishi Electric fr-e700 series, Instruction Manual

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Parameter Operation selection at power failure
FR-E700 SC EC/ENE 6 - 157
NOTES
Speed detection time (frequency search) changes according to the motor speed (maximum
100 ms).
Frequency search errors can occur if the output capacity of the frequency inverter is one or more
classes higher than that of the motor or if the motor is a special model (e.g. with a frequency rating
above 60 Hz). If this happens it is possible for overcurrent error messages (OCT) to be generated
during motor acceleration. In such configurations flying restarts are not possible and the fre-
quency search function should not be used.
At motor frequencies of 10 Hz or less the inverter accelerates from 0 Hz to the set frequency.
If more than one motor is connected to the inverter in parallel the frequency search on automatic
restart does not work correctly and overcurrent error messages (OCT) are likely. In such configura-
tions deactivate frequency search (set Pr. 162 to "1" or "11").
When reverse rotation is detected when Pr. 78 = "1" (reverse rotation disabled), the rotation direc-
tion is changed to forward rotation after decelerates in reverse rotation when the start command
is forward rotation. The inverter will not start when the start command is reverse rotation.
When automatic restart operation after instantaneous power failure is activated while the motor is
running at a low speed (less than 10 Hz), the motor restarts in the direction prior to instantaneous
power failure without detecting the rotation direction (Pr. 299 "Rotation direction detection selec-
tion at restarting" = "1").
If the frequency search result exceeds the set frequency, the output frequency is limited at the set
frequency.
When the wiring length exceeds 100 m, select without frequency search (Pr. 162 = "1" or "11").