Holding Brake; Brake Operating Sequence - YASKAWA SGD7S Product Manual

5.11

Holding Brake

A holding brake is used to hold the position of the moving part of the machine when the SER-
VOPACK is turned OFF so that moving part does not move due to gravity or an external force.
You can use the brake that is built into a Servomotor with a Brake, or you can provide one on
the machine.
The holding brake is used in the following cases.

Vertical Axis
• The brake built into a Servomotor with a Brake is a de-energization brake. It is used only to
hold the Servomotor and cannot be used for braking. Use the holding brake only to hold a Ser-
vomotor that is already stopped.
• The /BK signal will remain ON during overtravel. The brake will not be applied.
Important
5.11.1

Brake Operating Sequence

You must consider the time required to release the brake and the time required to brake to
determine the brake operation timing, as described below.
Time Required to Release Brake
The time from when the /BK (Brake) signal is turned ON until the brake is actually released.
Time Required to Brake
Term
The time from when the /BK (Brake) signal is turned OFF until the brake actually operates.
Servo ON command (Enable = 1)
Motor power status
Brake contact section
Position/speed reference
Servomotor

Holding brake

Prevents the moving part from
falling due to gravity when the
power supply is OFF.
Moving part of machine
Servo OFF
Power not
supplied.
OFF
/BK (Brake) signal
Brake
applied.
(lining)
*1
0
Motor speed
*2

Shaft with External Force Applied
Moving part of machine
External force
Servomotor
Prevents the moving part from
moving due to an external force.
Servo ON
Power supplied.
ON
Brake released.
*1
5.11 Holding Brake

5.11.1 Brake Operating Sequence

Holding brake
Servo OFF
Power not supplied.
*3
OFF
Brake applied.
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