
B-65262EN/03 SPECIFICATIONS FOR THE αiS/αi SERIES 6.BUILT-IN BRAKE
- 105 -
6.4 REDUCING THE BRAKE SHAFT FALL AMOUNT
During use of a motor with a brake, the amount of falling along an
axis at a power failure or emergency stop, or when the CNC power
supply is turned off during excitation of the motor may become an
issue. To operate the brake immediately and reduce the amount of
falling along an axis to a minimum, note the following points:
(1) To operate the brake immediately, the switch and relay for
controlling on and off must be installed on the DC side (at the
position shown in the following figure) of the break circuit.
If the contact is installed on the AC side (between the
transformer's secondary side and rectifier), it takes time until
braking starts because of the current returned to the rectifier
diodes.
(2) To reduce the amount of falling along a vertical axis, the switch
or relay must be turned off at a power failure as soon as possible.
To turn the relay off immediately at a power failure, it is
effective to supply the relay driving power from the main power
supply whenever possible as shown in the following figure.
(3) To prevent the shaft from falling during an emergency stop, it is
sometimes effective to use the "brake control function" in the
servo software. This function enables continuous excitation of
the motor until the motor built-in brake operates.
For details, see Parameter Manual (B-65270EN).
To other 24 VDC peripheral devices
(such as a relay and solenoid)
(CNCs and amplifiers not included)