Fuji Electric frenic mini series, User Manual

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G-2
If a deceleration time shorter than the natural
stopping time (coast-to-stop) determined by a
moment of inertia for a load machine, then the
motor works as a generator when it decelerates,
causing the kinetic energy of the load to be
converted to electrical energy that is returned to
the inverter from the motor. If this power
(regenerative power) is consumed or accumulated
by the inverter, the motor generates a braking force
called "braking torque."
Carrier frequency
Frequency used to modulate a modulated
frequency to establish the modulation period of a
pulse width under the PWM control system. The
higher the carrier frequency, the closer the inverter
output current approaches a sinusoidal waveform
and the
quieter the motor becomes.
Related function code: F26
Coast-to-stop
If the inverter stops its output when the motor is
running, the motor will coast to a stop due to
inertial force.
Constant feeding rate time
Time required for an object driven by the inverter
traverses in a constant distance previously defined.
The faster speed, the shorter time and vise versa.
This facility may be applied to a chemical process
that determines a processing time of materials as
the speed such as heating, cooling, drying, or
doping in some constant-speed machinery.
Related function codes: E39 and E50.
Constant output load
A constant output load is characterized by:
1) The required torque is in inverse proportion to
the load rpm
2) An essentially constant power requirement
Related function code: F37
Applications: Machine tool spindles
Constant torque load
A constant torque load is characterized by:
1) A requirement for an essentially constant
torque, regardless of the rpm
2) A power requirement that decreases in
proportion to the rpm
Related function code: F37
Applications: Conveyors, elevators, and transport
machines
Control circuit terminals
Terminals on the inverter, which are used for
input/output of signals to control the
inverter/external equipment directly or indirectly
Current Limiter
A device that keeps an inverter output frequency
within the set current limit.
Cursor
An indication that enables change/modification of
the digit. If a digit on the LED blinks, the cursor is
on the digit, and the digit can be changed/
modified.
Curvilinear V/f pattern
A generic name for the inverter output patterns
with curvilinear relation between the frequency
and voltage.
Refer to function code H07 in Chapter 9,
Subsection 9.2.5 "H codes."
DC injection braking
DC current braking that an inverter injects into the
motor to brake and stop it against the moment of
inertia of the motor or its load. The inertial energy
generated is consumed as heat in the motor.
If a motor having the load with large moment of
inertia is going to stop abruptly, the moment of
inertia may force to rotate the motor after the
inverter output frequency has been reduced to 0
Hz. Use DC injection braking to stop the motor
completely.
Related function codes: F20 and F21