Holding Brake; Brake Operating Sequence - YASKAWA SGD7S Product Manual

5.12

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 Servomotor
that is already stopped.
Important
5.12.1

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.
Term Time Required to Brake
The time from when the /BK (Brake) signal is turned OFF until the brake actually operates.
SV_ON (Servo ON) command
Motor power status
/BK (Brake) signal
Brake contact section
Position/speed reference
*1.
Rotary Servomotors: The brake delay times for Servomotors with Holding Brakes are given in the following
table. The operation delay times in the following table are examples for when the power supply is switched on
the DC side. You must evaluate the actual brake delay times on the actual equipment before using the applica-
tion.
Shaft with External Force Applied
Servomotor
External force

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
Brake
applied.
(lining)
*1
0
Motor speed
*2
Moving part of machine
Servomotor
Holding brake
Prevents the moving part from
moving due to an external force.
Servo ON
Servo OFF
Power supplied.
Power not supplied.
*3
ON
Brake released. Brake applied.
*1
5.12 Holding Brake

5.12.1 Brake Operating Sequence

OFF
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