Mitsubishi Electric FR-F700PJ Series Manual page 7

Optimum for Fan and Pump Applications
(1) Enhanced PID control
•To save energy in low-speed operation: PID output shutoff (sleep) function
•To shorten the start-up time of PID control: PID automatic switchover function
•For air conditioning applications: Forward/reverse rotation switching
•To use various types of detectors: PID set point and measured value
(Example: Water-cooling pump for a showcase)
(2) Regeneration avoidance function
The operation frequency is automatically increased to prevent the
regenerative overvoltage fault from occurring. This function is useful
when a load is forcibly rotated by another fan in the duct.
The fan is rotated by the external force.
We need smooth start-up
of the motor.
Use the
flying start function.
The motor can be started smoothly even after the motor was
rotated by the external force (coasting).
This function can be set enabled by changing
Power supply
Sudden change
of rotation
Motor
speed
Output
frequency
Without the function
Parameters to adjust the acceleration time at a restart (Pr.611), to
detect the fan rotation direction (Pr.299), etc. are also available.
by external signals
outputs in voltage (0 to 5V / 0 to 10V)
and current (4 to 20mA)
Pr.57 setting.
Power supply
Smooth
starting
Motor
speed
Output
frequency
With the function
(3) Automatic restart after instantaneous power
failure function / ying start function
After an instantaneous power failure, the operation is re-startable from
the coasting motor speed.
Even if the rotation direction has been forcibly reversed, the operation
can be smoothly restarted in the original direction.
We need continuous operations
without being interrupted by the
overvoltage protective function
Use the
regeneration avoidance function.
When the external force accelerates rotation of the running motor
(regeneration), the motor may trip due to the overvoltage.
The regeneration avoidance function is available to increase the
frequency and avoid the regenerative condition.
This function can be set enabled by changing
Motor
speed
OV trip
Bus voltage Bus voltage
Output
frequency
Without the function
Parameters to start the regeneration avoidance operation (Pr.883)
and to adjust the response level (Pr.886) are also available.
Coasts during
instantaneous
power failure
(E.OV).
Pr.822 setting.
Motor
speed
The trip does not occur and
the operation continues.
Output
frequency
With the function
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