Siemens SINAMICS S120 - Page 360

SINAMICS S120
Engineering Information
SINAMICS Engineering Manual – November 2015
Ó Siemens AG
360/528
SINAMICS S120 Smart Line Modules: Precharging by means of precharging contactor and precharging resistors
IMPORTANT:
It is absolutely essential that the precharging contactor and the bypass contactor are controlled by the internal
sequence control of the S120 Smart Line Module (precharging contactor via internal wiring and bypass contactor /
circuit breaker via connector -X9:3,4). When a circuit breaker is used, it is essential that breaker opening is controlled
by an instantaneous release. For this reason, only circuit breakers equipped with instantaneous undervoltage release
may be used.
For S120 Smart Line Modules in Chassis format, the fuse protection for the precharging circuit must be provided
externally by the customer. The fuses recommended for this purpose are listed in the table below.
Owing to the brief period of overlap when the precharging contactor and the bypass contactor are closed at the same
time, it is essential to ensure that the precharging circuit has the same phase sequence as the main circuit.
For S120 Smart Line Modules in Cabinet Modules format, the precharging circuit is always protected by fuses
contained in the Line Connection Module LCM that is connected upstream of the Smart Line Module.
The following table specifies the rms values of the line currents which occur at the beginning of the precharging
process in the case of line supply voltages 400 V or 690 V. Due to the principle of precharging using resistors, the
specified values apply irrespective of the DC link capacitance to be precharged. Where other line voltage values
apply, the line currents must be converted in proportion to the line voltage.
The specified precharging currents decay according to an e-function until the precharging process is completed after
a period of typically 1 to 2 s. Due to the temperature rise in the precharging resistors during the process, the
minimum permissible interval for complete precharging of the DC link is 3 minutes.
S120 SLM output
at
400 V or 690 V
Frame size Output
Input current
at
400 V or 690 V
Precharging
resistor R
p
per line phase
Line current at the beginning of
DC link precharging
(initial rms value)
at
400 V or 690 V
Recommended fuses
(provided externally)
to protect precharging
arm on S120 Chassis
380 V – 480 V 3AC
GX 250 kW 463 A 12 Ω 17 A 3NE1 817-0 (50A)
GX 355 kW 614 A 12 Ω 17 A 3NE1 817-0 (50A)
HX 500 kW 883 A 4 Ω 50 A 3NE1 817-0 (50A)
JX 630 kW 1093 A 4 Ω 50 A 3NE1 817-0 (50A)
JX 800 kW 1430 A 4 Ω 50 A 3NE1 817-0 (50A)
500 V – 690 V 3AC
GX 450 kW 463 A 12 Ω 29 A 3NE1 817-0 (50A)
HX 710 kW 757 A 4 Ω 86 A 3NE1 817-0 (50A)
JX 1000 kW 1009 A 4 Ω 86 A 3NE1 817-0 (50A)
JX 1400 kW 1430 A 4 Ω 86 A 3NE1 817-0 (50A)
S120 Smart Line Modules: Line currents at the beginning of precharging (initial rms values)