Mitsubishi Electric FR-A720-0.4K Instruction Manual page 205

DC injection
Pr.12
Operation
brake
voltage
voltage
Pr. 11 Operation time
DC injection
Pr. 12
Operation
brake
voltage
voltage
X13 signal
(3) Operation voltage (torque) setting (Pr. 12)
⋅ Use Pr. 12 to set the percentage to the power supply voltage. (This parameter is not used during zero speed control
or servo lock.)
⋅ When Pr. 12 = "0%", the DC injection brake is not operated. (At a stop, the motor coasts.)
⋅ When using the constant-torque motor (SF-JRCA) and energy saving motor (SF-HR, SF-HRCA), change the Pr. 12
setting as follows.
SF-JRCA: 3.7K or less ...4%, 5.5K to 55K...2%
SF-HR, SF-HRCA: 3.7K or less...4%, 5.5K and 7.5K...3%, 11K to 55K...2%
(30K...1.5%)
REMARKS
⋅ For the 5.5K and 7.5K, when the Pr. 12 setting is as below, changing the Pr. 71 Applied motor setting changes the Pr. 12 setting
automatically, it is not necessary to change the Pr. 12 setting.
(a) When Pr. 12 is 4% (initial value)
The Pr. 12 setting is automatically changed to 2% if the Pr. 71 value is changed from the value selecting the standard motor
(0, 2 to 8, 20, 23, 24, 40, 43, 44) to the value selecting the constant torque motor (1, 13 to 18, 50, 53, 54).
(b) When Pr. 12 is 2%
The Pr. 12 setting is automatically changed to 4% (initial value) if the Pr. 71 value is changed from the value selecting the
constant torque motor (1, 13 to 18, 50, 53, 54) to the value selecting the standard motor (0, 2 to 8, 20, 23, 24, 40, 43, 44).
(4) Brake operation selection during real sensorless vector control (Pr. 850)
⋅ You can select DC injection brake (initial value) or zero speed control for brake operation during real sensorless
vector control.
When Pr. 850 = "1", zero speed control is exercised when the frequency reaches or decreases below the frequency
set in Pr. 10.
REMARKS
⋅ When the X13 signal is on with Pr. 11 = "8888", zero speed control is activated regardless of setting of Pr. 850 Brake operation
selection.
⋅ When restarting from brake operation during real sensorless vector control, set "1" (zero speed control) in Pr. 850. When the
setting value is "0" (DC injection brake), it may take approx. 2s until frequency is actually output from when the start command
is input.
(1) Operation frequency setting (Pr. 10)
⋅ When the frequency at which the DC injection brake (zero speed control,
servo lock) operates is set in Pr. 10, the DC injection brake (zero speed
control, servo lock) is operated when this frequency is reached during
deceleration.
⋅ At the Pr. 10 setting of "9999", the DC injection brake (zero speed control,
servo lock) is operated when deceleration is made to the frequency set in
Pr. 13 Starting frequency.
Time
REMARKS
⋅ Performing pre-excitation (zero speed control) under real sensorless vector
Time
may cause motor vibration, etc. at deceleration to stop. To prevent this, set
Pr.10 DC injection brake operation frequency to 0.5Hz or less.
⋅ The initial value of Pr. 10 automatically changes to 0.5Hz during vector control.
(2) Operation time setting (X13 signal, Pr. 11)
⋅ Use Pr. 11 to set the duration period the DC injection brake (zero speed
control, servo lock) is applied.
⋅ When Pr. 11 = "0s", the DC injection brake (zero speed control, servo lock)
is not operated. (At a stop, the motor coasts.)
⋅ When Pr. 11= "8888", the DC injection brake (zero speed control, servo
lock) is applied when X13 signal is turned on.
⋅ For the terminal used for X13 signal input, set "13" in any of Pr. 178 to Pr.
Time
189 to assign the function. (Refer to page 221)
⋅ When the motor does not stop due to large load moment (J), increasing the
setting produces an effect.
Time
REMARKS
ON OFF
⋅ When the X13 signal is turned on with Pr. 11= "8888", zero speed control is
activated regardless of setting of Pr. 850 Brake operation selection.
⋅ Under vector control, zero speed control or servo rock is activated depending
on the Pr. 802 setting.
Motor brake and stop operation
4
195