Acceleration/Deceleration Time Setting; Dc Injection Brake, Zero Speed Control, Servo Lock; Motor Protection From Overheat; Starting Frequency - Mitsubishi Electric FR-A700 Manual

Pr.
Pr.
7, 8, 20, 21, 44, 45, 110, 111

Acceleration/deceleration time setting

Pr.7 Acceleration time
Pr.20 Acceleration/deceleration reference frequency
Pr.44 Second acceleration/deceleration time
Pr.110 Third acceleration/deceleration time
Used to set motor acceleration/deceleration time.
Set a larger value for a slower speed increase/decrease or a
smaller value for a faster speed increase/decrease.
Use Pr.7 Acceleration time to set the acceleration time taken to reach
Pr. 20 Acceleration/deceleration reference frequency from 0Hz.
Use Pr.8 Deceleration time to set the deceleration time taken to reach
0Hz from Pr.20 Acceleration/deceleration reference frequency.
Pr.20
(60Hz)
Running
frequency
Pr.7
Acceleration Deceleration
Pr.44
time
time
Pr.110
Pr.
Pr.
9, 51

Motor protection from overheat

(electronic thermal relay function )
Pr.9 Electronic thermal O/L relay
Set the current of the electronic thermal relay function to protect
the motor from overheat. This feature provides the optimum
protective characteristics, including reduced motor cooling
capability, at low speed.
Used to detect the motor overload (overheat) and stop the inverter
output transistor operation to stop the output.
Set the rated current [A] of the motor in Pr.9.
(When the power supply specification is 200V/220V(400V/440V) 60Hz,
set the 1.1 times the rated motor current.)
Set "0" in Pr.9 to make the electronic thermal relay function invalid
when using a motor with an external thermal relay, etc. (Note that
the output transistor protection of the inverter functions (E.THT).)
When using a Mitsubishi constant-torque motor
1) Set any of "1, 13 to 18, 50, 53, 54" in Pr.71. (This provides a
100% continuous torque characteristic in the low-speed range.)
2) Set the rated current of the motor in Pr.9.
When the RT signal is on, thermal protection is provided based on
the Pr.51 setting.
Use this function when running two motors of different rated currents
individually by a single inverter. (When running two motors together,
use external thermal relays.)
43
When setting parameters, refer to the instruction manual (applied) and understand instructions.
Pr.8 Deceleration time
Pr.21 Acceleration/deceleration time increments
Pr.45 Second deceleration time
Pr.111 Third deceleration time
Pr.21
Description
Setting
0
Increments:
0.1s
Increments and
(initial
Range:
setting range of
value)
0 to 3600s
acceleration/
deceleration
Increments:
Time
time setting can
0.01s
1
be changed.
Range:
Pr.8
0 to 360s
Pr.45
Pr.111
Pr.51 Second electronic thermal O/L relay
Pr.
Pr.
10 to 12, 802, 850

DC injection brake, zero speed control, servo lock

Pr.10 DC injection brake operation frequency
Pr.12 DC injection brake operation voltage
Pr.850 Brake operation selection
The DC injection brake can be operated at a motor stop to adjust
the stop timing and braking torque.
When "8888" is set in Pr. 11, DC brake is applied while X13 signal is
on.
Pr.12 is valid only under V/F control and advanced magnetic flux
vector control.
Time
Pr.12
DC injection
Operation
brake
voltage
voltage
Time
Pr.11 Operation time
DC brake (setting "0", initial value) and zero speed control (setting
"1") can be selected using Pr.850 under real sensorless vector
control.
This function selects either zero speed control or servo lock for
braking operation when pre-excitation is performed with the LX
signal during speed control operation under vector control. Turning
on the LX signal enables the pre-excitation function.
Braking
Pr.802 Setting
Operation
0
Zero speed
control
(initial value)
1
Servo lock
Set the frequency at which control changes to zero speed control or
servo lock control (select using Pr.802 ) in Pr.10 and operation time in Pr.11
during vector control.
The initial value of Pr.10 automatically changes to 0.5Hz during vector
control.
Pr.
Pr.
13, 571

Starting frequency

Pr.13 Starting frequency
You can set the starting frequency and hold the set starting
frequency for a certain period of time.
Set these functions when you need the starting torque or want
smooth motor drive at a start.
Output
frequency
(Hz)
60
Pr.13
0
Pr.571 setting time
Forward
rotation ON
Pr.11 DC injection brake operation time
Pr.802 Pre-excitation selection
When
When
Using the
Using the
Pr.12 Initial
Mitsubishi
Energy
Value
Constant
Saving
Torque
Motor
Motor
← ←
4%
3.7K or less
4% 2%* 3%
5.5K, 7.5K
← ←
2%
11K to 55K
← ←
75K or more 1%
* If the Pr.71 initial value is changed
to the setting for use with a
constant-torque motor, the Pr.12
setting changes to the
corresponding value in the above
table.
Description
Even under load, an attempt is made to
maintain 0r/min to keep the motor shaft
stopped.
Note that if the shaft is overcome and
turned by external force, it does not return
to the original position.
Even under load, an attempt is made to
maintain the motor shaft position.
Note that if the shaft is turned by external
force, it returns to the original position after
the external force has gone away.
Pr.571 Holding time at a start
Time