DC link components
7.2 Braking Module Booksize
SINAMICS S120 Combi
Manual, (GH9), 07/2016, 6SL3097-4AV00-0BP5
181
X21 digital inputs/outputs
Table 7- 9 X21 digital inputs/outputs
1 DI low: enable Braking Module
DI high: Inhibit/acknowledge
Edge change, high → low: fault acknowledgement
Voltage: -3 … +30 V
Current consumption typical:
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 activated manually
DI high: Braking resistor controlled manually
2)
If X21.1 and X21.2 are activated simultaneously,
the Braking Module inhibit has priority.
3 DO high: no prewarning
DO low: Prewarning, disconnection imminent
Max. load current per output: 100 mA
Continuously short-circuit proof
Voltage: 24 V DC
4 DO high: ready for operation, no fault
Ground
Type: Screw terminal 1 (Page 307)
Max. connectable cross-section 1.5 mm
2
Tightening torque: 0.22 … 0.25 Nm
DI: digital input; DO: digital output; M: Electronics ground
The fast discharge function is used for discharging the capacitors in the DC link after interruption of the line supply and
may be used a maximum of 1 to 2 times per week.
Terminal X21.1 - inhibit/acknowledge
Applying a high signal to terminal X21.1 inhibits the Braking Module. On a falling edge,
pending error signals are acknowledged.
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 of the Braking Module is 80 % of the maximum value.
● 80 % of the maximum on-load factor of the braking resistor has been reached (I
2
t
monitoring).
● 80 % of the maximum braking energy of the braking resistor has been reached.
● An incorrect braking resistor is connected (only braking resistors approved by Siemens
for this component are identified automatically).
In the event of an overtemperature, the error cannot be acknowledged until after a cooling
phase.