Siemens SINAMICS S120 Function Manual page 193

Operating brake for crane drives
For cranes with a manual control, it is important that the drive immediately re-
sponse when the control lever is moved (master switch). The drive is powered-up
using the on command (p0840) (the pulses are enabled). Speed setpoint (p1142)
and speed controller (p0856) are inhibited. The motor is magnetized. The magneti-
zation time generally applicable for three-phase motors (1–2 seconds) is therefore
eliminated.
Now, there is only the brake opening time that is applicable as delay between mo-
ving the master switch and the motor rotating. If the master switch is moved (de-
flected), then there is a "setpoint enable from the control" (bit interconnected with
p1142, p1229.2, p1224.0). The speed controller is immediately enabled – the
speed setpoint is enabled after the brake opening time (p1216). When the master
switch is in the zero position, the speed setpoint is inhibited – the drive is ramp-
down using the ramp-function generator. The brake closes once the standstill limit
(p1226) has been fallen below. After the brake closing time (p1217), the speed
controller is inhibited (the motor is now not generating any force!) The extended
brake control is used with the modifications described below.
[2704]
Brk close standst
p1224 [ 0]
<1>
[2707]
OR logic operation
Pulse enable
Extended brake control p1279 [0]
.3
r1229
p1279 [ 1]
<1>
[2711]
Enable n_set
p1142 [ C]
<1>
Setpoint 2 enable
p1152
Fig. 4-5 Example, operating brake for a crane drive
© Siemens AG 2006 All Rights Reserved
SINAMICS S120 Function Manual, 03/2006 Edition
p1275 .02 (1)
0
1
1
1
Enable speed setpoint
&
.
(r0899 15 )
"Extended brake control" function module
[2501]
Brake OR
logic operation Enable speed controller
result
p0856
.
r1229 10
r0898.6
<1> Setpoint enable from higher-
level control (e.g. S7) = enable
setpoint (master switch deflected)
Extended Functions
[xxxx] Function diagram number
4-193