Siemens SIRIUS 3RW40, Manual

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SIRIUS 3RW30 / 3RW40
Manual 01/2010, 535 1995-02 DS01
51
6
Application planning
6.1 Application examples
6.1.1 Roller conveyor application
Using the 3RW30 with roller conveyors
Roller conveyors are employed, for example, in parcel distribution systems for transporting
parcels to and from individual workstations. For this purpose, the direction of rotation of the 11
kW / 15 hp motor that is used has to be adjustable in order for the conveyor to work in both
directions.
The following requirements must be met by the roller conveyor:
• The roller conveyor has to start smoothly, to prevent damage to the transported goods due
to slipping or tilting.
• The machine's wear and maintenance intervals should be minimized, which is why
slippage of the belt drive during startup must be prevented.
• The high current load upon motor startup must be reduced by means of a voltage ramp.
• The feeder assembly should be as small as possible so as not to exceed the control
cabinet's space capacity.
The SIRIUS 3RW30 soft starter offers the following advantages:
• The roller conveyor is rapidly accelerated to the nominal speed without torque surges
thanks to the optimum setting of the voltage ramp during startup.
• The motor's starting current is reduced.
• Reversing operation of the conveyor belt is realized through contactor interconnection with
SIRIUS 3RA13 reversing contactor combinations.
• The feeder and the motor protection are implemented with SIRIUS 3RV motor starter
protectors.
• The use of SIRIUS system components guarantees maximum wiring reductions and
space savings.