Siemens SINAMICS S120 Equipment Manual page 123

Pre-charge contactor
The precharging contactor must be able to conduct the maximum precharging current for
approx. 1 second and be able to switch ohmic-capacitive loads.
To protect against overvoltage when opening, the contactor should be equipped with a
varistor, corresponding to the manufacturer's recommendations.
The precharging contactor is controlled via terminal -X9: VL1, VL2 of the Active Line
Modules Chassis-2.
An additional normally closed (NC contact) of the precharging contactor must be routed to
terminal -X47:1 to guarantee the feedback signal. The 24 V DC supply can be taken from
terminal strip -X42.
The following contactors are recommended:
● For a version with one precharging resistor for each phase, a Sirius 3RT2027 is
recommended.
● For a version with two precharging resistors connected in parallel for each phase, a Sirius
3RT2037 contactor is recommended.
● For a version with three precharging resistors connected in parallel for each phase, a
Sirius 3RT2037 contactor is recommended.
Precharging resistors
The precharging resistors are used to limit the current while precharging.
Table 4- 36
Category
Rated voltage
Frequency
Resistance value
Pulse energy
Precharging current
- one resistor per phase
- two resistors per phase in parallel
- three resistors per phase in parallel
Ambient temperature
Article number
The pulse energy may only occur every 3 minutes
1)
Line current available at the start of the precharging (initial rms value) at 400 V
2)
As the precharging resistors can get hot, sufficient cooling and clearance to adjacent
components must be ensured in operation.
Air-cooled chassis power units
Manual, 07/2019, 6SL3097-4AE00-0BP9
Technical data for the precharging resistors
1)
2)
Line-side power components
4.7 Active Interface Modules Chassis-2
Unit 3 AC 380 ... 480 V
V 690 VAC
Hz 47 ... 63
Ω 2.2 ±10%
Ws 18000
A
A
A
° C
6SL3000-0KE12-2AA0
91
182
274
60
121