Siemens SINAMICS S120 Function Manual page 336

Basic functions
8.12 Armature short-circuit
If the function is activated, then the following responses are executed:
1. Pulse cancellation is first activated,
2. then the external armature short-circuit braking is initiated. If the function has been
triggered, r0046.4 indicates a "1".
Example
The function is activated if the signal source of p1230 is set to "1". Then the following responses
are carried out:
1. The display parameters of drive object Motor Module r1239.0 and r0046.4 also indicate "1".
2. Pulse enable is deleted, and the contactor for the external braking is switched.
3. Braking starts as a result of the short-circuited armature.
4. Braking is terminated by setting the signal source of p1230 to "0" signal. As a consequence
r1239.0 also displays a "0" signal.
5. When the wait time p1237 expires, the pulse enables are output.
Calculating external braking resistors
To achieve the highest braking effect, calculate the values of the resistors using the following
formula:
● R
n
Parameterizing the function
You can parameterize Motor Modules and Control Units with the aid of an engineering tool (e.g.
Startdrive). The parameter lists of the drive objects and of the digital inputs/outputs are
available for this.
● Terminals 11 and 14 are connected to ground.
● The digital inputs/outputs DI/DO 8 to 15 are connected with terminals 9, 10, 12 and 13 at
terminal blocks X122 and X132. You can use parameters p0728[8...15] to define the
terminals as an input or output.
● Digital inputs DI 8 to 15 are interconnected with the parameters p0722[8...15] and can be
inverted with p0723[8...15].
● The outputs are interconnected with parameters p0738 to p0745.
● The outputs can be inverted with p0748[8...15] = 1.
● Parameters p0722 to p0748 are Control Unit parameters.
● Parameters p123x, r1239 and r0046 are drive parameters.
334
= 5.2882 · 10 · p0314 · p0356 · n
-5
ext
= maximum speed used
max
- p0350
max
Function Manual, 06/2019, 6SL3097-5AB00-0BP2
Drive functions