Line Contactors - Siemens SINAMICS S120 Equipment Manual

Fire or plant/system standstill when fault currents occur
Undetected fault currents in the power supply can result in fires with smoke and therefore
pose a hazard for persons or at least result in failures of the entire plant.
• Always install residual current protective devices in conjunction with suitable circuit
4.5

Line contactors

When selecting a line contactor, the characteristic values in the technical data apply. The
cables and conductors to be connected must be dimensioned in compliance with local
installation regulations.
NOTICE
Damage to the drive electronics when switching the line contactor under load
If you switch the line contactor (recommended type) under load, the contacts will wear out
prematurely. This may lead to faulty functioning of the contactor with subsequent damage
to the drive electronics.
• Use a leading, opening auxiliary contact.
• If this is not possible, avoid switching the line contactor under load.
Note
To limit the switching overvoltage, the contactor coil must be connected to a surge
suppression device (e.g. freewheeling diode or varistor).
When a digital output is used to control the line contactor, its switching capacity must be
taken into account.
AC Drive
Manual, 06/2019, 6SL3097-5AL00-0BP1
WARNING
breakers.
Mains connection and line-side power components
4.5 Line contactors
49