LSIS 6731001500, User Manual

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Learning Advanced Features
Speed search for general
acceleration
Initialization after a fault trip
Restart after instantaneous power
interruption
Starting with power-on
Speed search for general acceleration:
If bit 1 is set to ‘1’ and the inverter
operation command runs, acceleration starts with the speed search
operation. When the motor is rotating under load, a fault trip may occur if
the operation command is run for the inverter to provide voltage output.
The speed search function prevents such fault trips from occurring.
Initialization after a fault trip other than an LV trip:
If bit 2 is set to ‘1’ and
PRT-08 (RST Restart) is set to ‘1 (Yes)’, the speed search operation
automatically accelerates the motor to the operation frequency used before
the fault trip when the [Reset] key is pressed (or the terminal block is
initialized) after a fault trip.
Automatic restart after a power interruption:
If bit 3 is set to ‘1,’ and if a
low voltage trip occurs due to a power interruption but the power is
restored before the internal power shuts down, the speed search operation
accelerates the motor back to its frequency reference before the low
voltage trip.
If an instantaneous power interruption occurs and the input power is
disconnected, the inverter generates a low voltage trip and blocks the
output. When the input power returns, the operation frequency before the
low voltage trip and the voltage is increased by the inverter’s inner PI
control.
If the current increases above the value set at CON-72, the voltage stops
increasing and the frequency decreases (t1 zone). If the current decreases
below the value set at CON-27, the voltage increases again and the
frequency stops decelerating (t2 zone). When the normal frequency and
voltage are resumed, the speed search operation accelerates the motor
back to its frequency reference before the fault trip.