Siemens 3RK1308-0 00-0CP0 Series, Руководство по эксплуатации оборудования

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Functions
6.4 Motor control
Motor starter (3RK1308‑0**00‑0CP0)
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Equipment Manual, 11/2019, A5E34821005002A/RS-AC/003
6.4 Motor control
6.4.1 Electronic switching technology (hybrid switching technology)
The ET 200SP motor starter combines the advantages of semiconductor technology and
relay technology.
The ET 200SP motor starter switches the load in phases L1 and L2 via semiconductors and
bypass relays. Phase L3 is always switched via a relay.
DANGER
Hazardous Voltage
Can Cause Death or Serious Injury
If the line voltage is applied at the infeed bus of the motor starter, a hazardous voltage may
be active at the output of the motor starter even without a motor ON command. When
working on the feeder, you must ensure disconnection from the power, e.g. by the position
"Parking position/OFF".
You will find further information on the "Parking position/OFF" in the System Manual.
This combination is known as hybrid switching technology. Hybrid switching technology in
the ET 200SP motor starter is characterized by the following properties:
Switching on
The inrush current in the case of motorized loads is conducted briefly via the
semiconductors.
Advantage: The relay contacts are protected. Longer service life is achieved thanks to
reduced wear and tear.
Current routing
The continuous current is routed via relay contacts.
Advantage: Relay contacts cause lower thermal losses than semiconductors.
Switching off
Switching off is implemented via the semiconductors.
Advantage: The contacts are not stressed with arcs when switching via the semiconductors.
This results in increased service life.