Siemens SINAMICS GL150, Operating Instructions Manual

Page: 39 / 168

12-pulse operation has the following advantages:
● The low 12-pulse torque ripple is retained during starting in the DC-link pulsing range.
● The voltage of the DC link only rises in one system in the event of a ground fault or at the
motor. The voltage reaches no more than the peak value of the phase voltage of one
system.
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Figure 3-7 Circuit with typical harmonic spectrum
3.3.3.2 Fuseless technology
The converter is of fuseless design. In the event of a fault, limiting of the overcurrent at the input
terminals should be ensured by an appropriate transformer design. In addition, the converter
requires matched circuit breakers with a tripping time of 80 ms. The closed-loop control system
triggers the circuit breakers. Each circuit breaker must be equipped with a fail-safe OFF contact
and an undervoltage coil.
Internal current transformers sense the current and evaluate it electronically. The open-loop
and closed-loop control systems prevent an impermissible rise in any overcurrent by switching
the line-side converter to inverter operation.
NOTICE
Fault due to incorrect configuration of line supply and transformer impedances
On the line side, the converter is designed for short-circuit-proof operation. Short-circuit-proof
operation is only guaranteed if the line supply and transformer impedances are in
conformance with the respective specifications in the system-specific data.
If the supply and transformer impedances cannot be maintained, material damage to the
converter can occur.
Observe the system-specific values in the "Technical data and drawings" chapter.
Description
3.3 Power unit
SINAMICS GL150 6SL38555UN113KA0Z
Operating Instructions Rev.201910281450 EXAMPLE
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