SIEMENS
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Siemens IC 10 · 2017
SIRIUS 3RW Soft Starters
3RW44 for High Feature Applications
General data
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Overview
3RW44 soft starter with PROFINET communication module
In addition to soft starting and soft ramp-down, the solid-state
SIRIUS 3RW44 soft starters provide numerous functions for
higher-level requirements. They cover a performance range up
to 710 kW (at 400 V) in the inline circuit and up to 1200 kW
(at 400 V) in the inside-delta circuit.
The 3RW44 soft starters are characterized by a compact design
for space-saving and clearly arranged control cabinet layouts.
For optimized motor starting and stopping the innovative
SIRIUS 3RW44 soft starters are an attractive alternative with
considerable savings potential compared to applications with a
frequency converter. The new torque control and adjustable
current limiting enable the High Feature soft starters to be used
in nearly every conceivable task. They guarantee the reliable
avoidance of sudden torque applications and current peaks
during motor starting and stopping. This creates savings
potential when calculating the size of the switchgear and when
servicing the machinery installed. Be it for inline circuits or
inside-delta circuits – the SIRIUS 3RW44 soft starter offers
savings especially in terms of size and equipment costs.
The bypass contacts already integrated in the soft starter
bypass the thyristors after a motor ramp-up is detected. This
results in a further great reduction in the heat loss occurring
during operation of the soft starter at rated value.
Combinations of various starting, operating and ramp-down
possibilities ensure an optimum adaptation to the application-
specific requirements. Operation and commissioning can be
performed with the menu-controlled keypad and a menu-
prompted, multi-line graphic display with background lighting.
The optimized motor ramp-up and ramp-down can be effected
quickly, easily and reliably by means of just a few settings with a
previously selected language. Four-key operation and plain-text
displays for each menu point guarantee full clarity at every
moment of the parameterization and operation.
Applicable standards
•
IEC 60947-4-2
• UL/CSA
Functionality
Equipped with modern, ergonomic user prompting the 3RW44
soft starters can be commissioned quickly and easily using a
keypad and a menu-prompted, multi-line graphic display with
background lighting. The optimized motor ramp-up and ramp-
down can be effected quickly, easily and reliably by means of
just a few settings with a selectable language. Four-key
operation and plain-text displays for each menu point guarantee
full clarity at every moment of the parameterization and
operation. During operation and when control voltage is applied,
the display field continuously presents measured values and
operating values as well as warnings and fault messages. An
external display and operator module can be connected by
means of a connection cable to the soft starter, thus enabling
active indications and the like to be read directly from the control
cabinet door.
The SIRIUS 3RW44 soft starters are equipped with optimum
functionality. An integral bypass contact system reduces the
power loss of the soft starter during operation.
This reliably prevents heating of the switchgear environment.
The SIRIUS 3RW44 soft starters have internal intrinsic device
protection. This prevents thermal overloading of the power
section's thyristors, e.g. due to unacceptably high closing
operations.
Wiring outlay for installing an additional motor overload relay is
no longer needed as the SIRIUS 3RW44 soft starters perform
this function too. In addition they offer adjustable trip classes
and a thermistor motor protection function. As an option the
thyristors can also be protected by SITOR semiconductor fuses
from short-circuiting so that the soft starter is still functional after
a short circuit (type of coordination "2"). And even inrush current
peaks are reliably avoided thanks to adjustable current limiting.
Optionally, SIRIUS 3RW44 soft starters can be upgraded with a
PROFIBUS DP or PROFINET module. Thanks to their communi-
cation capability and their programmable control inputs and
relay outputs the SIRIUS 3RW44 soft starters can be very easily
and quickly integrated in higher-level controllers.
In addition a creep speed function is available for positioning
and setting jobs. With this function the motor can be controlled
in both directions of rotation with reduced torque and an
adjustable, low speed.
On the other hand the SIRIUS 3RW44 soft starters offer a new,
combined DC braking function for the fast stopping of driving
loads.
© Siemens AG 2016