Mitsubishi Electric FR-E700EX Instruction Manual page 134

Motor brake and stop operation
(3) Torque setting during DC injection brake operation (Pr.795)
 In Pr.795, set the maximum torque that can be generated during DC injection brake operation.
 When a value exceeding 50% is set, motor overload trip (E.THM) may occur depending on the DC injection brake (pre-
excitation) operation time.
(4) Servo-ON signal (SON signal)
 Turning ON the SON signal turns ON the base circuit to set the drive unit ready for operation (servo-ON status). Turning
OFF the SON signal turns OFF the base circuit to cause the motor to coast.
 Turning ON the SON signal activates zero speed control, servo lock or DC injection brake while the motor is stopped.
(Initial magnetic pole detection is performed if the SON signal is turned from OFF to ON during a stop.)
 When the SON signal is assigned to an input terminal, the SON signal must be ON to accept the start signal (STF or STR
signal). Additionally, when the SON signal is assigned to an input terminal, the pre-excitation signal (LX signal) is invalid.
 The SON signal is valid in all the operation modes. For example, even in the PU operation mode, the operation cannot be
started with the SON signal OFF.
 To assign the SON signal, set "86" in any of Pr.178 to Pr.184 (input terminal function selection).
 When the operation becomes ready by turning ON the SON signal, the operation ready 2 signal (RY2) is turned ON. The
output shutoff signal (MRS signal) is OFF.
For the operation ready 2 signal (RY2), assign the function by setting "33 (positive logic) or 133 (negative logic)" in any of
Pr.190 to Pr.192 (output terminal function selection).
(5) Pre-excitation signal (LX signal)
 Turning ON the LX signal activates zero speed control, servo lock or DC injection brake while the motor is stopped.
 The deceleration-to-a-stop operation commanded by the LX signal decelerates the motor to 0r/min, then zero speed
control, servo lock or DC injection brake is performed, regardless of the Pr.10 and Pr.11 settings.
 Initial magnetic pole detection is not performed for the startup from the pre-excitation status, eliminating the startup delay.
(Initial magnetic pole detection is performed if the LX signal is turned from OFF to ON during a stop.)
 To assign the LX signal, set "23" in any of Pr.178 to Pr.184 (input terminal function selection).
 The operation ready 2 signal (RY2) turns ON at the start of pre-excitation.
The signal stays ON as long as pre-excitation is activated even if the drive unit is in a stop status. The output shutoff
signal (MRS signal) is OFF.
For the operation ready 2 signal (RY2), assign the function by setting "33 (positive logic) or 133 (negative logic)" in any of
Pr.190 to Pr.192 (output terminal function selection).
(6) Brake operation selection (Pr.802)

Select the brake operation when pre-excitation is activated under speed control between zero speed control and servo
lock by Pr.802. Under position control, servo lock is activated regardless of the Pr.802 setting.
Pr.802 setting Pre-excitation
Zero speed
0 (initial value)
control
1 Servo lock
132
Even under a load, the drive unit does not rotate the motor and holds 0r/min. However, once an
external force has rotated the shaft, the shaft is not returned to the original position.
This setting is invalid under position control. The drive unit operates according to this setting only
under speed control.
Even under a load, the drive unit holds the position of the motor shaft. Even after an external force
has rotated the shaft, the shaft is returned to the original position.
Because position control is performed, the position loop gain can be adjusted in Pr.422 Position
control gain. Additionally, unstable movement (vibration) can be prevented by adjusting Pr.698 Speed
control D gain.
Description