7-13
7-5 Brake Interlock
OMNUC G5-series AC Servomotors and Servo Drives User’s Manual (with Built-in EtherCAT Communications)
  7
Applied Functions
7-5 Brake Interlock
This function lets you set the output timing for the brake interlock output (BKIR) that activates
the holding brake when the servo is turned ON, an error occurs, or the servo is turned OFF.
The brake can also be controlled via EtherCAT communications.
Objects Requiring Settings
*1 The Brake Interlock Output (BKIR) is turned ON. The brake is released for a brake release command from either
EtherCAT communications or the Servo Drive. 
*2 The Brake Interlock Output (BKIR) is turned OFF. The brake is engaged only when a set brake command is received
from both EtherCAT communications and the Servo Drive. 
Applying the brake from EtherCAT communications is enabled only while the servo is OFF. If a Set Brake command
is received while the servo is ON, a Command Warning (B1 hex) will occur. 
Precautions for Correct Use
 The brake on a Servomotor with a brake is a normally closed brake designed only to hold when
the operation is stopped. Accordingly, set an appropriate time so that the brake actuates after the
motor stops.
 If the brake is engaged while the Servomotor is rotating, the brake disc will wear abnormally or
sustain damage, resulting in a bearing or encoder failure in the Servomotor.
 The workpiece may fall when the brake is released for a vertical axis. Carefully consider the timing
of releasing the brake. 
Index Sub-index Bit Name Explanation Reference
3437 hex - -
Brake Timing when 
Stopped
Set the time after a servo OFF command is 
issued upon servo lock stop, until the brake 
interlock output (BKIR) turns OFF and 
power supply stops.
page 9-29
3438 hex - -
Brake Timing 
During Operation
Set the time after a servo OFF command is 
issued while the motor is rotating, until the 
brake interlock output (BKIR) turns OFF and 
power supply stops. If the speed drops to or 
below the value set in object 3439 hex 
before the time set here, BKIR will turn OFF.
page 9-29
3439 hex - -
Brake Threshold 
Speed During 
Operation
Set the speed at which to turn OFF power to 
the Servomotor when the Brake Interlock 
Output (BKIR) signal turns OFF after 
execution of a servo OFF command while 
the Servomotor is rotating. If the time set in 
object 3438 hex elapses before the 
Servomotor drops to the speed set here, 
BKIR will turn OFF. 
page 9-30
60FE hex
01 hex 0
This is the Set Brake Bit for EtherCAT 
communications. 
0: Brake released
*1
1: Brake engaged
*2
page 6-50
02 hex 0
This is the Set Brake Mask Bit for enabling/
disabling the Set Brake Bit for EtherCAT 
communications. 
0: Set Brake Bit enabled. 
1: Set Brake Bit disabled.