Siemens SINAMICS S120 - Page 98

Communication via PROFIBUS
Cyclic communication
4-98
E Siemens AG, 2004. All rights reserved
SINAMICS S120 Installation and Start-Up Manual, 12/04 Edition
TRQRED (torque reduction)
This setpoint can be used to reduce the torque limit currently active on the drive.
When you use manufacturer-specific PROFIBUS telegrams with the TRQRED
control word, the signal flow is automatically interconnected up to the point where
the torque limit is scaled.
profibus_momred.vsd
(1543)
p1528
(1520)
p1522
p1520
T_limit_1
p1520
(1543)
p1529
(1521)
p1523
p1521
T_limit_2
p1521
p2050[4]
3
2
1
6
TRQDER
4
...
p1543(2050[4])
p1542
1 – (p1544 * x)
p1544
p1543(2050[4])
p1542
1 – (p1544 * x)
p1544
Scaling
Scaling
e.g.
by 10 %
10 % to 90 %
––> 100 % == 4000 hex
10 % to 90 %
––> 100 % == 4000 hex
Fig. 4-9 TRQRED setpoint
TRQRED specifies the percentage by which the torque limit is to be reduced. This
value is converted internally to the amount by which the torque is to be reduced
and normalized via p1544.