Motor Brake And Stop Operation; Dc Injection Brake Of General-Purpose Motor Control (Pr. 10 To Pr. 12) <V/F><S Mfvc - Mitsubishi Electric FR-F720P-0.75K to 110K Instruction Manual

4.10 Motor brake and stop operation

Purpose
Motor braking torque adjustment
Motor braking torque adjustment
Improve the motor braking torque with an
option
Performing operation by DC current input DC current feeding mode
Coast the motor to a stop
4.10.1 DC injection brake of general-purpose motor control (Pr. 10 to Pr. 12)
S S S
V/F V/F V/F MFVC MFVC MFVC
The DC injection brake can be operated at a motor stop to adjust the stop timing and braking torque.
In DC injection brake operation, DC voltage is directly applied to the motor to prevent the motor shaft from
rotating when a motor decelerates to stop.
The motor will not return to the original position if the motor shaft rotates due to external force.
Parameter
Name
Number
DC injection brake
10
operation frequency
DC injection brake
11
operation time
12
DC injection brake
V/F V/F V/F
operation voltage
S S S
MFVC MFVC MFVC
The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 201)
Pr.12
DC injection
Operation
brake
voltage
voltage
Pr. 11 Operation time
(3) Operation voltage (torque) setting (Pr. 12)
⋅ Use Pr. 12 to set the percentage to the power supply voltage.
⋅ When Pr. 12 = "0%", the DC injection brake is disabled. (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 lower ...4%, 5.5K to 55K...2%
SF-HR, SF-HRCA: 3.7K or lower...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, 120, 210) to the value selecting the constant motor (1).
(b) When Pr. 12 is 2%
The Pr. 12 setting is automatically changed to 4% if the Pr. 71 value is changed from the value selecting the constant motor
(1) to the value selecting the standard motor (0, 2, 120, 210).
⋅ Even if the Pr. 12 setting is increased, braking torque is limited so that the output current is within the rated inverter current.
DC injection brake of general-
purpose motor control
DC injection brake of IPM motor
control
Selection of a regenerative brake
Selection of motor stopping method
Output stop function
< V / F > < S M F V C >
Initial Value
3Hz
0.5s
7.5K or lower
11K to 55K
75K or higher
(1) Operation frequency setting (Pr. 10)
⋅
When the frequency at which the DC injection brake will be operated is set
to Pr. 10, the DC voltage is applied to the motor upon reaching to the set
frequency during deceleration.
⋅ At the Pr. 10 setting of "9999", the DC injection brake is operated when
deceleration is made to the frequency set in Pr. 13 Starting frequency.
(2) Operation time setting (Pr. 11)
Time
⋅ In Pr. 11, set the time of the DC injection brake.
⋅ When Pr. 11 = "0s", the DC injection brake is disabled. (At a stop, the
motor coasts.)
Time
⋅ When the motor does not stop due to large load moment (J), increasing
the setting produces an effect.

Motor brake and stop operation

Parameter that must be set
Pr. 10 to Pr. 12
Pr. 10, Pr. 11
Pr. 30, Pr. 70
Setting
Range
Set the operation frequency of the DC injection
0 to 120Hz
brake.
9999 Operated at Pr. 13 or less.
0 DC injection brake disabled
0.1 to 10s Set the operation time of the DC injection brake.
4%
Set the DC injection brake voltage (torque). When
2%
0 to 30%
"0" is set, DC injection brake is disabled.
1%
Refer to Page
123
124
125
Pr. 30 125
Pr. 250 130
Pr. 522 131
Description
4
123