S1 - Threshold Switch - Siemens SINAMICS S120 Manual

Options
8.32 L61/L62, L64/L65, braking units
Note
Applying a high signal level to "DI inhibit input" inhibits the Braking Module. On a falling
edge, pending error messages are acknowledged.
The "DO fault output" signal can be used for evaluation in the Control Unit.
On the "+24 V" signal, 24 V DC must be provided by the customer to supply the Braking
Module.
8.32.3

S1 - Threshold switch

The response threshold at which the Braking Module is activated and the DC link voltage
generated during braking is specified in the following table.
The threshold switch position may be changed only when the Basic Line, Smart Line,
Active Line, or Motor Module are switched off and the DC link capacitors are discharged.
Table 8- 54 Response thresholds of the Braking Modules
Rated Response
voltage threshold
380 V – 673 V
480 V
774 V
500 V – 841 V
600 V
967 V
660 V – 1070 V
690 V
1158 V
436
WARNING
Switch Comments
position
1 774 V is the default factory setting. With line voltages of between 380 and 400 V,
the response threshold can be set to 673 V to reduce the voltage stress on the
2
motor and converter. This does, however, reduce the possible braking power with
the square of the voltage (673/774)² = 0.75.
The maximum possible braking power is, therefore, 75%.
1 967 V is the default factory setting. With a line voltage of 500 V, the response
threshold can be set to 841 V to reduce the voltage stress on the motor and
2
converter. This does, however, reduce the possible braking power with the
square of the voltage (841/967)² = 0.75.
The maximum possible braking power is, therefore, 75%.
1 1158 V is the default factory setting. With a line voltage of 660 V, the response
threshold can be set to 1070 V to reduce the voltage stress on the motor and
2
converter. This does, however, reduce the possible braking power with the
square of the voltage (1070/1158)² = 0.85.
The maximum possible braking power is, therefore, 85%.
Cabinet Modules
Manual, (GH5), 05/2010, A5E03263538A