Technical data • Motor options (ff)
20
8JSA user's manual V1.00
8.3 Holding brake (ff)
Operating principle
The holding brake is a spring-applied brake controlled by a B&R drive system. Based on principle, this type of
holding brake exhibits a minimal amount of backlash.
The brake is designed as a holding brake. It not permitted to be used for operational braking! Under these condi-
tions, the brake has a service life of approximately 5,000,000 cycles (opening and closing the brake is one cycle).
Loaded braking during an emergency stop is permitted but reduces its service life.
Information:
The required brake holding torque is determined based on the actual load torque. If not enough infor-
mation is known about the load torque, it is recommended to assume a safety factor of 2.
Warning!
The holding brake is not intended for normal braking. The holding brake does not provide protection
for personnel. The maximum motor torque far exceeds the holding torque for the brake.
Motor options (ff) - Overview (order code)
see "Motor options (ff)" on page 18
Standard holding brake (ff)
All 8JSA three-phase synchronous motors can be delivered with a holding brake. It is in-
stalled directly behind the B bearing on the motor and used to hold the motor shaft when
no power is applied to the servo motor.
Technical data - Standard holding brake
Description
Motor size
2
3
4
5
6
7
Holding torque M
Br
[Nm]
1.42
2.5
5.3
14.5
25
53
Connected load P
On
[W]
8.4 ±7%
10.1 ±7%
12.8 ±7%
19.5 ±7%
25.7 ±7%
35.6 ±7%
Supply current I
On
[A]
0.35
0.42
0.53
0.82
1.07
1.48
Supply voltage U
On
[V] (+6% /
-10%)
24 VDC
24 VDC
24 VDC
24 VDC
24 VDC
24 VDC
Moment of inertia J
Br
[kgcm²]
0,011
0,011
0,068
0,173
0.61
1.64
Weight m
Br
[kg]
0.27
0.35
0.63
1.1
2
2.9