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Siemens 3RW4073-6BB44 — Soft Starters

Siemens 3RW4073-6BB44 SIRIUS Soft Starter, 230A at 40°C

MPN3RW4073-6BB44

Siemens SIRIUS 3RW4073-6BB44 soft starter, size S12, 230 A at 40 °C, 205 A at 50 °C, 180 A at 60 °C, 230 V control supply, thyristor-switched, adjustable current limitation, motor overload protection.

$1,710.00 – $2,171.70Ref. price · indicative, final on quote
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

3RW4073-6BB44 — Identification
ParameterValue
Product designationSoft starter
Product brand nameSIRIUS
3RW4073-6BB44 — Power & Motor Rating
ParameterValue
Rated operational current at 40 °C230A
Rated operational current at 50 °C205A
Rated operational current at 60 °C180A
Rated insulation voltage600V
Minimum settable current (% of Ie)20%
3RW4073-6BB44 — Control & Connection
ParameterValue
Control supply voltage typeAC
Rated voltage at 50 Hz230V
Rated voltage at 60 Hz230V
Main circuit terminal typebusbar connection
Auxiliary contact rating (UL)B300 / R300
Control supply voltage tolerance, AC 50 Hz (max.)10%
Control supply voltage tolerance, AC 50 Hz (min.)-15%
Control supply voltage tolerance, AC 60 Hz (max.)10%
Control supply voltage tolerance, AC 60 Hz (min.)-15%
Control supply frequency tolerance (max.)10%
Control supply frequency tolerance (min.)-10%
Operating frequency tolerance (max.)10%
Operating frequency tolerance (min.)-10%
3RW4073-6BB44 — Protection & Features
ParameterValue
Motor overload protectionYes
Thermistor motor protectionNo
Adjustable current limitationYes
Inside-delta connectionNo
Intrinsic device protectionYes
Pollution degree3, acc. to IEC 60947-4-2
3RW4073-6BB44 — Mechanical
ParameterValue
Height230mm
Width160mm
Depth278mm
Mounting positionWith additional fan: With vertical mounting surface +/-90° rotatable, with vertical mounting surface +/- 22.5° tiltable to the front and back Without additional fan: With vertical mounting surface +/-10° rotatable, with vertical mounting surface +/- 10° t
Fastening methodscrew fixing
Mounting clearance, top100mm
Mounting clearance, bottom75mm
Mounting clearance, side5mm
3RW4073-6BB44 — Environmental
ParameterValue
Operating temperature range-25 ... +60°C
Ambient class during operation (IEC 60721)3K6 (no formation of ice, no condensation), 3C3 (no salt mist), 3S2 (sand must not get into the devices), 3M6
Ambient class during transport (IEC 60721)2K2, 2C1, 2S1, 2M2 (max. fall height 0.3 m)

Product details

Derate to 205 A at 50 °C and 180 A at 60 °C — the thermal limit governs the real-world install, so size for the ambient in your enclosure. Operating frequency range is 50 to 60 Hz, covering standard line frequencies globally. Built-in motor overload protection and adjustable current limitation let you set the start current profile without an external overload relay. An external reset input is provided for remote restart after a fault trip. Intrinsic device protection monitors internal temperature and faults — no separate motor PTC needed for the starter itself.

Dimensions: 230 mm high, 160 mm wide, 278 mm deep. Mounts via screw fixing to a vertical panel surface. With the additional fan, the mounting surface can be rotated up to +/-90° and tilted +/-22.5° front-to-back. Without the fan, rotation is limited to +/-10° and tilt to +/-10°. Clearance requirements: 100 mm above, 75 mm below, 5 mm at the sides. Main current circuit connects via busbar connection. Wire ranges: stranded 70 to 240 mm², finely stranded 50 to 240 mm². For kcmil terminations, the front clamping point accepts 3/0 to 600 kcmil, the back clamping point 250 to 500 kcmil, and using both clamping points together accepts 2/0 to 500 kcmil per side. Auxiliary contacts accept 20 to 14 AWG solid wire. Maximum motor cable length is 300 m — keep this in mind for long runs to avoid voltage drop affecting the soft starter's commutation. Derating begins at 40 °C. Not configured for inside-delta circuit wiring — this is a standard in-line soft starter.

Frequently asked questions

What are the key current ratings for this soft starter?

Rated 230 A at 40 °C, derated to 205 A at 50 °C, and 180 A at 60 °C. The 40 °C figure is the headline rating; the 50 °C and 60 °C values govern real-world installs in warm enclosures.

What is the physical size and mounting method?

Size S12, measuring 230 mm high, 160 mm wide, 278 mm deep. Mounts with screw fixing to a vertical panel. Clearance: 100 mm above, 75 mm below, 5 mm at the sides.

What wire sizes does it accept for power connections?

Stranded 70 to 240 mm², finely stranded 50 to 240 mm². For kcmil: front clamp 3/0 to 600 kcmil, back clamp 250 to 500 kcmil, both clamps 2/0 to 500 kcmil per side.

Does it include motor overload protection?

Yes, built-in motor overload protection and adjustable current limitation are standard. An external reset input allows remote restart after a fault.

MPN
3RW4073-6BB44