Siemens SINAMICS S120

DC link components
8.3 Braking Module Booksize Compact
Booksize Power Units
Manual, (GH2), 07/2016, 6SL3097-4AC00-0BP8
505
8.3.3.3
X21 digital inputs/outputs
Table 8- 10 X21 digital inputs/outputs
Terminal
Designation
1)
Technical data
1 DI low: Enable Braking Module
DI high: inhibit/acknowledge
Edge change, high → low: fault acknowledgement
Voltage: -3 … +30 V
Typical current drain:
10 mA at 24 V DC
Level (incl. ripple)
High level: 15 … 30 V
Low level: -3 … +5 V
2 DI low: braking resistor, not controlled manually
DI high: Braking resistor controlled manually (quick
discharge)
2)
If X21.1 and X21.2 are activated simultaneously,
the Braking Module inhibit has priority.
3 DO high: no prewarning
DO low: Prewarning:
Max. load current per output: 100 mA
Continuously short-circuit proof
Voltage: 24 V DC
4 DO high: ready for operation, no fault
DO low: Fault
5
Ground
6
Type: Screw terminal 1 (Page 730)
1)
DI: digital input; DO: digital output; M: Electronics ground
2)
The "fast discharge function" is used for discharging the capacitors in the DC link after the line supply has been inter-
rupted.
Terminal X21.1 - inhibit/acknowledge
Applying a high signal to terminal X21.1 inhibits the Braking Module. Fault messages that
are available are acknowledged with a falling edge.
Terminal X21.3 - prewarning
When a prewarning is sent, disconnection of the braking module is imminent. This may be
due to the following causes:
● The temperature switch braking resistor has triggered (only if the "Braking resistor with
thermostatic switch" setting is used)
● The temperature of the Braking Module is 80 % of the maximum value.
● The I
2
t counter of the Braking Module has reached 80 % of the maximum value.
● The braking resistor has reached 80 % of the maximum permissible braking energy (only
for setting "Braking resistor without thermostatic switch").
● An incorrect braking resistor is connected (only if the "braking resistor without a
thermostatic switch" setting is used).