• Features
The space required by the compact SIRIUS 3RW30 softstarter is often only about one third of that required by a contactor assembly for wye-delta starting of comparable rating
This not only saves space in the control cabinet and on the standard mounting rail but also does away completely with the wiring work needed for wye-delta starters
This is notable in particular for higher motor ratings which are only rarely available as fully wired solutions
Compact dimensions, short start up times, easy wiring and fast commissioning make themselves felt as clear-cut cost advantages
The bypass contacts of these softstarters are protected during operation by an integrated solid state arc quenching system
The new series of devices comes with the polarity balancing control method, which is designed to prevent direct current components in 2-phase controlled softstarters
On two-phase controlled soft starters the current resulting from superimposition of the two controlled phases flows in the uncontrolled phase
This results for physical reasons in an asymmetric distribution of the three phase currents during the motor ramp-up, This phenomenon cannot be influenced, but in most applications it is non-critical
Controlling the power semiconductors results not only in this asymmetry, however, but also in the previously mentioned direct current components which can cause severe noise generation on the motor at starting voltages of less than 50 %
It creates a motor ramp-up that is uniform in speed, torque and current rise, thus permitting a particularly gentle, two-phase starting of the motors
At the same time the acoustic quality of the starting operation comes close to the quality of a three phase controlled soft starter. This is made possible by the on-going dynamic harmonizing and balancing of current halfwaves of different polarity during the motor ramp-up. Hence the name polarity balancing
Soft starting with voltage ramp; the starting voltage setting range Us ranges from 40 to 100 %, and the ramp time tR can be set from 0 to 20 s
Integrated bypass contact system to minimize power loss, Setting with two potentiometers, Simple mounting and commissioning
The built-in auxiliary contact ensures user-friendly control and possible further processing within the system
Cost-efficient operation Reduction of current peaks, Avoidance of mains voltage fluctuations during starting, Reduced load on the power supply network, Reduction of the mechanical load in the operating mechanism
Considerable space savings and reduced wiring compared with conventional starters, Maintenance-free switching, Very easy handling
Soft starting/ramp-down, voltage ramp and integral bypass contact system standard application
screw and snap-on mounting
6.5 A at 40 deg C Current
1 hp at 200/208 V 6 A, 1 hp at 220/230 V 6 A, 3 hp at 460/480 V 6 A