Bk (Brake Output) Signal; Stopping Methods; Alm (Servo Alarm) Signal - YASKAWA SGD7S Product Manual

11.2.9

/BK (Brake Output) Signal

If the HWBB operates when the /HWBB1 or /HWBB2 signal is OFF, the /BK (Brake) signal will
turn OFF. At that time, the setting in Pn506 (Brake Reference - Servo OFF Delay Time) will be
disabled. Therefore, the Servomotor may be moved by external force until the actual brake
becomes effective after the /BK signal turns OFF.
 The brake signal is not a safety-related element. You must design the system so that a haz-
ardous condition does not occur even if the brake signal fails in the HWBB state. Also, if a
Servomotor with a Brake is used, keep in mind that the brake in the Servomotor is used only
to prevent the moving part from being moved by gravity or an external force and it cannot
be used to stop the Servomotor.

11.2.10 Stopping Methods

If the /HWBB1 or /HWBB2 signal turns OFF and the HWBB operates, the Servomotor will stop
according to the stop mode that is set for stopping the Servomotor when the servo turns OFF
(Pn001 = n.X). However, if the dynamic brake is enabled (Pn001 = n.0 or
n.1), observe the following precautions.
 The dynamic brake is not a safety-related element. You must design the system so that a
hazardous condition does not occur even if the Servomotor coasts to a stop in the HWBB
state. Normally, we recommend that you use a sequence that returns to the HWBB state
after stopping for a reference.
 If the application frequently uses the HWBB, stopping with the dynamic brake may result in
the deterioration of elements in the SERVOPACK. To prevent internal elements from deterio-
rating, use a sequence in which the HWBB state is returned to after the Servomotor has
come to a stop.

11.2.11 ALM (Servo Alarm) Signal

The ALM (Servo Alarm) signal is not output in the HWBB state.
11.2 Hard Wire Base Block (HWBB)
CAUTION
CAUTION

11.2.9 /BK (Brake Output) Signal

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