3RW30Active
SIRIUS 3RW30 soft starter
SIRIUS 3RW30
Compact two-phase Siemens soft starter for motors up to 55 kW at 400 V (3.6 to 106 A), with voltage ramp and integral bypass for easy starting duty
سافت‌استارتر
© Siemens AG
siriusSeries 3RW55Active
SIRIUS 3RW55 soft starter
SIRIUS 3RW55
Three-phase High Performance Siemens soft starter from 5.5 to 710 kW (up to 1200 kW in inside-delta) with torque control, pump stop, braking, colour HMI, network modules and a Failsafe version with STO
Price and delivery time are given after a technical review.
Overview
Overview
SIRIUS 3RW55 is the High Performance soft starter from Siemens, made for the hardest starting and stopping jobs. Unlike the 3RW30 and 3RW40 it controls all three phases and, besides the voltage ramp, it has torque control: instead of raising the voltage it can ramp the motor torque itself. Hybrid switching with an integral bypass keeps losses to a minimum after starting. A removable HMI with a colour display and a microSD slot, and plug-in communication modules, make the device configurable and connectable to a network.
Read more
Range
13 to 1280 A rated current in five frame sizes, equal to motors from 5.5 to 710 kW at 400 V in the standard circuit. In an inside-delta circuit (six wires to the motor) the current through the soft starter is lower, so a smaller device is enough and the power reaches 1200 kW. The operational voltage is 200 to 480 V, with versions for 200 to 600 V (size 1) and 200 to 690 V (sizes 2 to 4). The control supply is 24 V AC/DC or 110 to 250 V AC.
What it has that the 3RW30 and 3RW40 do not
Starting with the voltage ramp or torque control, each with current limiting, and a breakaway pulse for loads with high static friction. Stopping with voltage ramp, torque control, pump stop and DC braking (dynamic without a contactor, with a braking contactor, or reversing), where the device activates the contactors it needs itself. Automatic parameterization for loads whose starting conditions change, condition monitoring (dry-running pump, loss of lubricating film, bearing damage) and a pump cleaning function. Motor overload protection with trip classes 10A, 10E, 20E and 30E. PROFINET modules (Standard, and High Feature with an integrated switch for a ring with media redundancy), PROFIBUS, EtherNet/IP and Modbus, and configuration with Soft Starter ES in TIA Portal.
The Failsafe version
The 3RW55 Failsafe has a fail-safe digital input to which an EMERGENCY STOP can be wired directly, and it implements Safe Torque Off (STO) with a restart interlock in the soft starter itself, from 5.5 to 315 kW in the standard circuit and up to 560 kW in inside-delta. According to the 2019 Siemens catalogue it covers SIL 1 / PL c on its own and reaches SIL 3 / PL e with an external contactor and safety relay.
Where it is needed
In the Siemens selection table the 3RW55 is the only recommended choice for a pump with a special stop against water hammer and for ultra-heavy starting (CLASS 30: large fans, saws, centrifuges, mills, crushers), and it is also recommended for agitators, extruders and turning and milling machines (CLASS 20). If the motor is up to 55 kW and the job is simple, the 3RW30 or 3RW40 is enough.
Soft starter or frequency converter
The 3RW55 is the closest a soft starter comes to a drive, but its running speed is still line speed. According to Siemens there is no general answer: when variable speed is not needed the soft starter is the first choice, and when it is, a frequency converter such as the SINAMICS G120 is the right answer.
Features
- Three-phase control with hybrid switching and an integral bypass
- 13 to 1280 A rated current in five sizes; motors 5.5 to 710 kW (400 V) and up to 1200 kW in inside-delta
- Starting with voltage ramp or torque control, each with current limiting, plus a breakaway pulse
- Stopping with voltage ramp, torque control, pump stop and DC braking
- Automatic parameterization, condition monitoring and a pump cleaning function
- Removable HMI with a colour display and a microSD slot
- Communication modules for PROFINET, PROFIBUS, EtherNet/IP and Modbus
- Configuration with Soft Starter ES in TIA Portal
- Failsafe version with a fail-safe input and integrated STO
Advantages
- One device for jobs the 3RW30 and 3RW40 cannot do: ultra-heavy starting up to CLASS 30 and a special pump stop
- Braking without extra engineering: the soft starter activates the braking or reversing contactor itself
- Automatic parameterization makes variable loads such as conveyor belts easier to start
- Condition monitoring from motor current and power, for example for a dry-running pump or bearing damage
- On the Failsafe version an EMERGENCY STOP is wired directly, saving components and wiring
- In inside-delta a smaller soft starter is enough and an existing star-delta wiring can be reused almost unchanged
Models and codes
| Model | Order code | Code type | Attributes | Request |
|---|---|---|---|---|
| SIRIUS 3RW5515, size 1, 25 Aسایز ۱، موتور ۱۱ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۴۸۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال پیچی برای مدار فرمان | 3RW5515-1HA14 | Exact code |
| Request SIRIUS 3RW5515, size 1, 25 A |
| SIRIUS 3RW5517, size 1, 38 Aسایز ۱، موتور ۱۸٫۵ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۴۸۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال پیچی برای مدار فرمان | 3RW5517-1HA14 | Exact code |
| Request SIRIUS 3RW5517, size 1, 38 A |
| SIRIUS 3RW5526, size 2, 77 Aسایز ۲، موتور ۳۷ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۴۸۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال پیچی برای مدار فرمان | 3RW5526-1HA14 | Exact code |
| Request SIRIUS 3RW5526, size 2, 77 A |
| SIRIUS 3RW5527, size 2, 93 Aسایز ۲، موتور ۴۵ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۶۹۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال پیچی برای مدار فرمان | 3RW5527-1HA16 | Exact code |
| Request SIRIUS 3RW5527, size 2, 93 A |
| SIRIUS 3RW5534, size 3, 113 Aسایز ۳، موتور ۵۵ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۶۹۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال پیچی برای مدار فرمان | 3RW5534-6HA16 | Exact code |
| Request SIRIUS 3RW5534, size 3, 113 A |
| SIRIUS 3RW5545, size 4, 315 Aسایز ۴، موتور ۱۶۰ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۶۹۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال فنری برای مدار فرمان | 3RW5545-2HA16 | Exact code |
| Request SIRIUS 3RW5545, size 4, 315 A |
| SIRIUS 3RW5553, size 5, 720 Aسایز ۵، موتور ۴۰۰ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۴۸۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال پیچی برای مدار فرمان | 3RW5553-6HA14 | Exact code |
| Request SIRIUS 3RW5553, size 5, 720 A |
| SIRIUS 3RW5558, size 5, 1280 Aسایز ۵، موتور ۷۱۰ کیلووات در ۴۰۰ ولت (مدار معمولی)، ولتاژ کاری ۲۰۰ … ۴۸۰ ولت، تغذیهٔ کنترل ۱۱۰ … ۲۵۰ ولت AC و ترمینال پیچی برای مدار فرمان | 3RW5558-6HA14 | Exact code |
| Request SIRIUS 3RW5558, size 5, 1280 A |
| SIRIUS 3RW5513 Failsafe, size 1, 13 Aنسخهٔ Failsafe با ورودی دیجیتال ایمنی و STO داخلی، سایز ۱، ۱۳ آمپر (۵٫۵ کیلووات در ۴۰۰ ولت)، ولتاژ کاری ۲۰۰ تا ۴۸۰ ولت، تغذیهٔ کنترل ۲۴ ولت AC/DC و ترمینال فنری برای مدار فرمان؛ در Industry Mall با وضعیت PM300 (Active) فهرست شده است | 3RW5513-3HF04 | Exact code |
| Request SIRIUS 3RW5513 Failsafe, size 1, 13 A |
| SIRIUS 3RW55, rest of the rangeساختار کد 3RW55: چهار رقم نوع و جریان (از 3RW5513 تا 3RW5558)، نوع اتصال مدار فرمان (۱ یا ۳ برای سایز ۱ و ۲؛ ۶ یا ۲ برای سایز ۳ و ۴)، HA برای استاندارد یا HF برای Failsafe، تغذیهٔ کنترل (۰: ۲۴ ولت AC/DC، ۱: ۱۱۰ تا ۲۵۰ ولت AC) و ولتاژ کاری (۴: تا ۴۸۰، ۵: تا ۶۰۰، ۶: تا ۶۹۰ ولت). کد دقیق از روی جریان موتور و این ساختار انتخاب می‌شود | 3RW5513-1H… | Example code |
| Request SIRIUS 3RW55, rest of the range |
Technical specifications
Check the specifications against the data sheet of the exact code before ordering.
| Motor rating at 400 VMotor rating at 400 V | 5.5 … 710 (standard circuit); up to 1200 (inside-delta) kW |
|---|---|
| Rated operational current Ie (40 °C)Rated operational current Ie (40 °C) | 13 … 1280 A |
| Frame sizesFrame sizes | Size 1 … 5 (3RW551 … 3RW555) |
| Rated operational voltageRated operational voltage | 200 … 480; versions 200 … 600 (size 1) and 200 … 690 (sizes 2 … 4) V AC |
| Performance classPerformance class | High Performance |
| Motor controlMotor control | Three-phase, hybrid switching with integral bypass |
| CircuitCircuit | Standard (in-line) or inside-delta |
| Start modesStart modes | Voltage ramp or torque control, each with current limiting; breakaway pulse |
|---|---|
| Stop modesStop modes | Coasting, voltage ramp, torque control, pump stop, DC braking (dynamic, with contactor, reversing) |
| Basis of the rated dataBasis of the rated data | CLASS 10E (normal starting) |
| Heavy and ultra-heavy startingHeavy and ultra-heavy starting | Recommended up to CLASS 30 (large fans, saws, centrifuges, mills, crushers) |
| Application functionsApplication functions | Automatic parameterization, condition monitoring, pump cleaning |
| Control supply voltageControl supply voltage | 24 V AC/DC or 110 … 250 V AC |
|---|---|
| Control circuit terminalsControl circuit terminals | Screw or spring-type, set by the order code |
| Motor overload protectionMotor overload protection | Electronic, CLASS 10A / 10E / 20E / 30E |
|---|---|
| Intrinsic device protectionIntrinsic device protection | Integrated |
| Short-circuit protectionShort-circuit protection | Not integrated; fuses or a motor starter protector are required |
| Failsafe versionFailsafe version | Fail-safe input F-DI, STO with restart interlock; SIL 1 / PL c alone, up to SIL 3 / PL e with contactor and safety relay |
| Failsafe motor rating at 400 VFailsafe motor rating at 400 V | 5.5 … 315 (standard circuit); up to 560 (inside-delta) kW |
| Communication modulesCommunication modules | PROFINET Standard, PROFINET High Feature (integrated switch, ring), PROFIBUS, EtherNet/IP, Modbus RTU, Modbus TCP |
|---|---|
| HMIHMI | Removable; colour display, local interface, microSD slot |
| Engineering softwareEngineering software | SIRIUS Soft Starter ES (TIA Portal) |
| Selection toolsSelection tools | Simulation Tool for Soft Starters (STS); TIA Selection Tool |
| DimensionsDimensions | Size 1 170 × 275 × 152; sizes 2 and 3 185 × 306 × 203; size 4 210 × 393 × 203 mm (W×H×D) |
|---|---|
| Ambient temperatureAmbient temperature | -25 … +60 in operation (derating above 40); -40 … +80 in storage °C |
| Installation altitudeInstallation altitude | Derating from 1000; max. 5000 (200 … 480 and 600 V versions), 2000 (690 V versions) m |
Modules and accessories
HMI High Feature
Removable HMI with a colour display, local interface and microSD slot for configuration and monitoring on site
PROFINET Standard communication module
PROFINET communication module (Standard version) for connection to the automation system
PROFINET High Feature communication module
PROFINET module with an integrated two-port switch that enables a ring with media redundancy and keeps communicating over the second port even if the power fails
PROFIBUS communication module
PROFIBUS communication module
EtherNet/IP communication module
EtherNet/IP communication module for connection to process control systems
Modbus RTU and Modbus TCP communication modules
Modbus RTU and Modbus TCP communication modules
Fan covers
Optional fan covers for sizes 3RW551 to 3RW554
HMI door-mounting kit and connecting cable
Kit for mounting the HMI in a cabinet door to IP65, and the cable connecting the HMI to the soft starter
Documents
- View on the manufacturer's site(opens in a new tab)
Manual
SIRIUS 3RW55 and 3RW55 Failsafe soft starters, manual
SIRIUS 3RW55 and 3RW55 Failsafe soft starters, manual
Language: English · Version 04/2026
- View on the manufacturer's site(opens in a new tab)
Manual
SIRIUS 3RW5 PROFINET communication module, manual
SIRIUS 3RW5 PROFINET communication module, manual
Language: English
- View on the manufacturer's site(opens in a new tab)
Manual
SIRIUS 3RW5 PROFIBUS communication module, manual
SIRIUS 3RW5 PROFIBUS communication module, manual
Language: English
- View on the manufacturer's site(opens in a new tab)
Manual
SIRIUS 3RW5 EtherNet/IP communication module, manual
SIRIUS 3RW5 EtherNet/IP communication module, manual
Language: English
- View on the manufacturer's site(opens in a new tab)
Catalog
SIRIUS Industrial Controls catalog IC 10, chapter 6: soft starters
SIRIUS Industrial Controls catalog IC 10, chapter 6: soft starters
Language: English · Version 2022
- View on the manufacturer's site(opens in a new tab)
Catalog
Catalog IC 10 A (abridged): SIRIUS 3RW soft starters
Catalog IC 10 A (abridged): SIRIUS 3RW soft starters
Language: English · Version 04/2018
- View on the manufacturer's site(opens in a new tab)
Brochure
SIRIUS 3RW55 Failsafe soft starters with integrated Safe Torque Off (SICP-B10024-00)
SIRIUS 3RW55 Failsafe soft starters with integrated Safe Torque Off (SICP-B10024-00)
Language: English · Version 2019
- View on the manufacturer's site(opens in a new tab)
Brochure
SIRIUS soft starters: as versatile as your application (brochure CPBR-3RSS-0620)
SIRIUS soft starters: as versatile as your application (brochure CPBR-3RSS-0620)
Language: English · Version 06/2020
- View on the manufacturer's site(opens in a new tab)
Brochure
SIRIUS Hybrid: starting motors with SIRIUS (flyer SIEP-B10001-00)
SIRIUS Hybrid: starting motors with SIRIUS (flyer SIEP-B10001-00)
Language: English
- View on the manufacturer's site(opens in a new tab)
Other
Siemens press release on the 3RW50 and 3RW55 Failsafe soft starters
Siemens press release on the 3RW50 and 3RW55 Failsafe soft starters
Language: English · Version 11/2019
- View on the manufacturer's site(opens in a new tab)
Software
Simulation Tool for Soft Starters (STS)
Simulation Tool for Soft Starters (STS)
Language: English
Official manufacturer links
- Official pageصفحهٔ رسمی سافت‌استارترهای SIRIUS 3RW در siemens.com(opens in a new tab)
- Industry MallSiemens Industry Mall، سافت‌استارتر 3RW5553-6HA14(opens in a new tab)
- Supportپشتیبانی Siemens: دفترچهٔ 3RW55 و 3RW55 Failsafe(opens in a new tab)
- Supportپشتیبانی Siemens: صفحهٔ مرجع سافت‌استارترهای 3RW(opens in a new tab)
Applications
- Water and wastewater pumps, with pump stop and pump cleaning
- Conveyor belts and handling systems with changing loads
- Agitators, extruders, turning and milling machines (heavy starting, CLASS 20)
- Large fans, circular and band saws, centrifuges, mills and crushers (ultra-heavy starting, CLASS 30)
- Compressors and fans at high power
- Saws with DC braking for a fast stop
- Replacing star-delta at high power, in the inside-delta circuit
- Machines and lines that need a safety-related emergency stop (STO)
Frequently asked questions
How does the 3RW55 differ from the 3RW30, the 3RW40 and the other SIRIUS soft starters?
Siemens arranges the SIRIUS soft starters in three classes. Basic Performance (3RW30, 3RW40 and 3RW50) is two-phase and meant for standard jobs; General Performance (3RW52) is three-phase and meant to replace star-delta; High Performance (3RW55) is three-phase with torque control, pump stop, braking, automatic parameterization, a colour HMI and network modules, and is the only class with a Failsafe version. The 3RW30 has the voltage ramp only and the 3RW40 adds soft stop and motor protection; both stop at 55 kW, the 3RW50 covers 75 to 315 kW and the 3RW55 goes to 710 kW (1200 in inside-delta).
When is the 3RW55 needed and when is the 3RW40 enough?
If the motor is up to 55 kW and the load starts normally or heavily at CLASS 20, the 3RW40 is enough. Choose the 3RW55 for: power above 55 kW, ultra-heavy starting at CLASS 30 (large fans, saws, centrifuges, mills, crushers), a pump with a special stop against water hammer, braking, a network connection (PROFINET, PROFIBUS, EtherNet/IP, Modbus) with setting and monitoring from the HMI or TIA Portal, or STO. Before choosing, simulate the load and motor with the Siemens Simulation Tool for Soft Starters (STS).
What is the 3RW55 Failsafe and what safety level does it give?
A version of the 3RW55 with a fail-safe digital input (F-DI) to which an EMERGENCY STOP is wired directly, and which performs Safe Torque Off (STO) with a restart interlock without a separate safety relay and contactor. According to the 2019 Siemens catalogue it covers SIL 1 / PL c on its own and reaches SIL 3 / PL e with an external contactor and safety relay; the Siemens flyer says up to SIL 3, PL e. Read the exact condition for each level in the 3RW55 manual. The rating of this version is 5.5 to 315 kW in the standard circuit and up to 560 kW in inside-delta.
Standard circuit or inside-delta: which should I choose?
In the standard circuit the soft starter has three wires and the wiring is simpler, but the full motor current flows through it and a larger device is needed. In the inside-delta circuit six wires go to the motor and the current through the soft starter is lower (in the Siemens table a 13 A device is enough for a motor drawing 22.5 A in inside-delta), so a smaller and cheaper device is enough; if the drive was star-delta before, the existing wiring stays almost the same. For the 3RW55, check both in the selection table.
Does the 3RW55 have short-circuit protection?
No. The 3RW55 data sheet states that the soft starter has no short-circuit protection; fuses or a motor starter protector must be provided separately. Motor overload protection and intrinsic device protection are in the device.
When should I choose a frequency converter such as the SINAMICS G120 instead?
When the motor has to run at different speeds in operation, or the process needs speed and torque accuracy. Even with torque control and braking the 3RW55 does not change the running speed. According to Siemens, when variable speed is not needed the soft starter is the first choice: less capital, space and maintenance, simpler wiring and no extra heat after starting.
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