Holding Brake; Brake Operating Sequence - YASKAWA E-7S SERVOPACK 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 brake release delay time and the brake operation delay time to deter-
mine the brake operation timing, as described below.
Brake Release Delay Time
The time from when the /BK (Brake) signal is turned ON until the brake is actually released.
Brake Operation Delay Time
Term
The time from when the /BK (Brake) signal is turned OFF until the brake actually operates.
/S-ON (Servo ON) signal
Motor power status
/BK (Brake) signal
Brake contact section
Position/speed reference
Motor speed
*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.
Servomotor

Holding brake

Prevents the moving part from
falling due to gravity when the
power supply is OFF.
Moving part of machine
OFF
Power not
supplied.
OFF
Brake applied.
*1
(lining)
0
*2

Shaft with External Force Applied
Moving part of machine
External force
Servomotor
Prevents the moving part from
moving due to an external force.
ON OFF
Power not supplied.
Power supplied.
*3
ON
OFF
Brake released.
Brake applied.
*1
5.11 Holding Brake

5.11.1 Brake Operating Sequence

Holding brake
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