How to Select and Size a Soft Starter for a Motor
How to size a soft starter correctly by full-load current, IEC 60947-4-2 duty class, starting torque against the load, control method, wiring topology and...
| Motor power kW | Rated current In (A) | Part number | Stock | Price |
|---|---|---|---|---|
| 77 | 3RW5526-1HF14 | On request | $2,946.85 | |
| 93 | 3RW5527-1HF14 | On request | $3,224.69 | |
| 113 | 3RW5534-6HF14This part | On request | $3,623.19 | |
| 143 | 3RW5535-6HF14 | On request | $4,323.66 | |
| 171 | 3RW5536-6HF14 | On request | $5,024.13 |
The Siemens 3RW5534-6HF14 is a soft starter from the SENTRON/SIRIUS 3RW5 series. SIRIUS soft starter 200-480 V 113 A, 110-250 V AC, Screw terminals Fail-safe. Supplied by Stoklink for industrial and commercial low-voltage applications.
The Siemens 3RW5534-6HF14 is used in industrial control panels, distribution boards and automation systems. As part of the Siemens 3RW5 range it integrates with compatible SENTRON/SIRIUS components for a coordinated low-voltage installation. Genuine Siemens product supplied by Stoklink with fast dispatch from Türkiye.
| product brand name | SIRIUS |
|---|---|
| product category | Hybrid switching devices |
| product designation | Failsafe soft starters |
| product type designation | 3RW55 |
| manufacturer's article number: of high feature HMI module usable | 3RW5980-0HF00 |
| manufacturer's article number: of communication module PROFINET standard usable | 3RW5980-0CS00 |
| manufacturer's article number: of communication module PROFIBUS usable | 3RW5980-0CP00 |
| manufacturer's article number: of communication module Modbus TCP usable | 3RW5980-0CT00 |
| manufacturer's article number: of communication module Ethernet/IP | 3RW5980-0CE00 |
| manufacturer's article number: of circuit breaker usable at 400 V | 3VA2216-7MN32-0AA0; Type of coordination 1, Iq = 65 kA, CLASS 10 |
| manufacturer's article number: of the gG fuse usable up to 690 V | 3NA3244-6; Type of coordination 1, Iq = 65 kA |
| manufacturer's article number: of the gG fuse usable at inside-delta circuit up to 500 V | 3NA3244-6; Type of coordination 1, Iq = 65 kA |
| manufacturer's article number: of full range R fuse link for semiconductor protection usable up to 690 V | 3NE1225-0; Type of coordination 2, Iq = 65 kA |
| manufacturer's article number: of back-up R fuse link for semiconductor protection usable up to 690 V | 3NE3231; Type of coordination 2, Iq = 65 kA |
| manufacturer's article number: of the redundant contactor for applications > SIL 1 according to EN 62061 | 3RT1056 |
| starting voltage [%] | 20 ... 100 % |
|---|---|
| stopping voltage [%] | 50 %; non-adjustable |
| start-up ramp time of soft starter | 0 ... 360 s |
| ramp-down time of soft starter | 0 ... 360 s |
| start torque [%] | 10 ... 100 % |
| stopping torque [%] | 10 ... 100 % |
| torque limitation [%] | 20 ... 200 % |
| current limiting value [%] adjustable | 125 ... 800 % |
| breakaway voltage [%] adjustable | 40 ... 100 % |
| breakaway time adjustable | 0 ... 2 s |
| number of parameter sets | 3 |
| accuracy class | 5 (based on IEC 61557-12) |
| certificate of suitability: CE marking | Yes |
| certificate of suitability: UL approval | Yes |
| certificate of suitability: CSA approval | Yes |
| product component: HMI-High Feature | Yes |
| product component: is supported HMI-High Feature | Yes |
| product feature integrated bypass contact system | Yes |
| number of controlled phases | 3 |
| current unbalance limiting value [%] | 10 ... 60 % |
| ground-fault monitoring limiting value [%] | 10 ... 95 % |
| buffering time in the event of power failure: for main current circuit | 100 ms |
| buffering time in the event of power failure: for control circuit | 100 ms |
| idle time adjustable | 0 ... 255 s |
| insulation voltage rated value | 480 V |
| degree of pollution | 3, acc. to IEC 60947-4-2 |
| impulse voltage rated value | 6 kV |
| blocking voltage of the thyristor maximum | 1 400 V |
| service factor | 1.15 |
| surge voltage resistance rated value | 6 kV |
| maximum permissible voltage for protective separation: between main and auxiliary circuit | 480 V; does not apply for thermistor connection |
| shock resistance | 15 g / 11 ms, from 6 g / 11 ms with potential contact lifting |
| vibration resistance | 15 mm up to 6 Hz; 2 g up to 500 Hz |
| recovery time after overload trip adjustable | 60 ... 1 800 s |
| utilization category according to IEC 60947-4-2 | AC 53a |
| reference code according to IEC 81346-2 | Q |
| Substance Prohibitance (day/month/year) | 11/22/2019 |
| SVHC substance name | Lead CAS-No. 7439-92-1 Lead monoxide (lead oxide) CAS-No. 1317-36-8 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one CAS-No. 71868- 10-5 Melamine CAS-No. 108-78-1 6,6'-di-tert-butyl-2,2'-methylenedi-p-cresol CAS-No. 119-47-1 Dibutylbis(pentane-2,4-dionato-O,O')tin CAS-No. 22673-19-4 |
| product function: ramp-up (soft starting) | Yes |
| product function: soft stopping | Yes |
| product function: breakaway pulse | Yes |
| product function: adjustable current limitation | Yes |
| product function: creep speed in both directions of rotation | Yes |
| product function: pump stop | Yes |
| product function: DC braking | Yes |
| product function: motor heating | Yes |
| product function: min/max pointer | Yes |
| product function: trace function | Yes |
| product function: intrinsic device protection | Yes |
| product function: motor overload protection | Yes; Full motor protection (thermistor motor protection and electronic motor overload protection) / When using the motor overload protection according to ATEX, an upstream contactor is required in inside-delta circuit. |
| product function: evaluation of thermistor motor protection | Yes; Type A PTC or Klixon / Thermoclick |
| product function: inside-delta circuit | Yes |
| product function: auto-RESET | Yes |
| product function: manual RESET | Yes |
| product function: remote reset | Yes |
| product function: communication function | Yes |
| product function: operating measured value display | Yes |
| product function: event list | Yes |
| product function: error logbook | Yes |
| product function: via software parameterizable | Yes |
| product function: via software configurable | Yes |
| product function: screw terminal | Yes |
| product function: spring-loaded terminal | No |
| product function: PROFIenergy | Yes; in connection with the PROFINET Standard and PROFINET High-Feature communication modules |
| product function: firmware update | Yes |
| product function: removable terminal for control circuit | Yes |
| product function: voltage ramp | Yes |
| product function: torque control | Yes |
| product function: combined braking | Yes |
| product function: analog output | Yes; 4 ... 20 mA (default) / 0 ... 10 V |
| product function: programmable control inputs/outputs | Yes |
| product function: condition monitoring | Yes |
| product function: automatic parameterisation | Yes |
| product function: application wizards | Yes |
| product function: alternative stopping mode | Yes |
| product function: emergency operation mode | Yes |
| product function: reversing operation | Yes |
| product function: soft starting at heavy starting conditions | Yes |
| operational current: at 40 °C rated value | 113 A |
|---|---|
| operational current: at 40 °C rated value minimum | 23 A |
| operational current: at 50 °C rated value | 101 A |
| operational current: at 60 °C rated value | 89 A |
| operational current at inside-delta circuit: at 40 °C rated value | 196 A |
| operational current at inside-delta circuit: at 50 °C rated value | 175 A |
| operational current at inside-delta circuit: at 60 °C rated value | 154 A |
| operating voltage: rated value | 200 ... 480 V |
| operating voltage: at inside-delta circuit rated value | 200 ... 480 V |
| relative negative tolerance of the operating voltage | -15 % |
| relative positive tolerance of the operating voltage | 10 % |
| relative negative tolerance of the operating voltage at inside-delta circuit | -15 % |
| relative positive tolerance of the operating voltage at inside-delta circuit | 10 % |
| operating power for 3-phase motors: at 230 V at 40 °C rated value | 30 kW |
| operating power for 3-phase motors: at 230 V at inside-delta circuit at 40 °C rated value | 55 kW |
| operating power for 3-phase motors: at 400 V at 40 °C rated value | 55 kW |
| operating power for 3-phase motors: at 400 V at inside-delta circuit at 40 °C rated value | 110 kW |
| Operating frequency 1 rated value | 50 Hz |
| Operating frequency 2 rated value | 60 Hz |
| relative negative tolerance of the operating frequency | -10 % |
| relative positive tolerance of the operating frequency | 10 % |
| minimum load [%] | 10 %; Relative to set Ie |
| power loss [W] for rated value of the current at AC: at 40 °C after startup | 34 W |
| power loss [W] for rated value of the current at AC: at 50 °C after startup | 30 W |
| power loss [W] for rated value of the current at AC: at 60 °C after startup | 27 W |
| power loss [W] at AC at current limitation 350%: at 40 °C during startup | 1 500 W |
| power loss [W] at AC at current limitation 350%: at 50 °C during startup | 1 279 W |
| power loss [W] at AC at current limitation 350%: at 60 °C during startup | 1 074 W |
| type of the motor protection | Electronic, tripping in the event of thermal overload of the motor |
| Part number | 3RW5534-6HF14 |
|---|---|
| Type designation | 3RW55 |
| Brand | Siemens |
| Condition | New, factory sealed |
| Source | Siemens and its authorised distributors |
| Warranty | Manufacturer warranty |
| Lifecycle status | Active, in production |
| EAN | 4047621040646 |
| ETIM class | EC000640 |
| eCl@ss | 27370907 |
| type of voltage of the control supply voltage | AC |
|---|---|
| control supply voltage at AC: at 50 Hz | 110 ... 250 V |
| control supply voltage at AC: at 60 Hz | 110 ... 250 V |
| relative negative tolerance of the control supply voltage at AC at 50 Hz | -15 % |
| relative positive tolerance of the control supply voltage at AC at 50 Hz | 10 % |
| control supply voltage frequency | 50 ... 60 Hz |
| relative negative tolerance of the control supply voltage frequency | -10 % |
| relative positive tolerance of the control supply voltage frequency | 10 % |
| control supply current in standby mode rated value | 100 mA |
| holding current in bypass operation rated value | 180 mA |
| inrush current by closing the bypass contacts maximum | 0.8 A |
| inrush current peak at application of control supply voltage maximum | 43 A |
| duration of inrush current peak at application of control supply voltage | 1.6 ms |
| design of the overvoltage protection | Varistor |
| design of short-circuit protection for control circuit | 4 A gG fuse (Icu=1 kA), 6 A quick-acting fuse (Icu=1 kA), C1 miniature circuit breaker (Icu= 600 A), C6 miniature circuit breaker (Icu= 300 A); Is not part of scope of supply |
| number of digital inputs | 4 |
|---|---|
| with fail-safe | 1 |
| parameterizable | 4 |
| number of digital outputs | 3 |
| Number of digital outputs with fail-safe | 1 |
| number of digital outputs parameterizable | 2 |
| number of digital outputs not parameterizable | 1 |
| digital output version | 2 normally-open contacts (NO) / 1 normally-closed contact (NC) / 1 changeover contact (CO) |
| number of analog outputs | 1 |
| switching capacity current of the relay outputs: at AC-15 at 250 V rated value | 3 A |
| switching capacity current of the relay outputs: at DC-13 at 24 V rated value | 1 A |
| OFF-delay time with safety-related request when switched off via control inputs maximum | 100 ms |
|---|
| mounting position | Vertical (can be rotated +/- 90° and tilted forward or backward +/- 22.5°) |
|---|---|
| fastening method | screw fixing |
| height | 306 mm |
| width | 185 mm |
| depth | 203 mm |
| required spacing with side-by-side mounting: forwards | 10 mm |
| required spacing with side-by-side mounting: backwards | 0 mm |
| required spacing with side-by-side mounting: upwards | 100 mm |
| required spacing with side-by-side mounting: downwards | 75 mm |
| required spacing with side-by-side mounting: at the side | 5 mm |
| weight without packaging | 6.85 kg |
| type of electrical connection: for main current circuit | busbar connection |
|---|---|
| type of electrical connection: for control circuit | screw-type terminals |
| width of connection bar maximum | 25 mm |
| wire length for thermistor connection: with conductor cross-section = 0.5 mm2 maximum | 50 m |
| type of connectable conductor cross-sections: for DIN cable lug for main contacts stranded | 2x (16 ... 95 mm2) |
| type of connectable conductor cross-sections: for control circuit solid | 1x (0.5 ... 4.0 mm2), 2x (0.5 ... 2.5 mm2) |
| type of connectable conductor cross-sections: for AWG cables for control circuit solid | 1x (20 ... 12), 2x (20 ... 14) |
| wire length: between soft starter and motor maximum | 800 m |
| wire length: at the digital inputs at DC maximum | 1 000 m |
| tightening torque: for main contacts with screw-type terminals | 10 ... 14 N·m |
| tightening torque: for auxiliary and control contacts with screw-type terminals | 0.8 ... 1.2 N·m |
| tightening torque [lbf·in]: for main contacts with screw-type terminals | 89 ... 124 lbf·in |
| tightening torque [lbf·in]: for auxiliary and control contacts with screw-type terminals | 7 ... 10.3 lbf·in |
| installation altitude at height above sea level maximum | 2 000 m |
|---|---|
| ambient temperature: during operation | -25 ... +60 °C; Please observe derating at temperatures of 40 °C or above |
| ambient temperature: during storage and transport | -40 ... +80 °C |
| environmental category: during operation according to IEC 60721 | 3K6 (no ice formation, only occasional condensation), 3C3 (no salt mist), 3S2 (sand must not get into the devices), 3M6 |
| environmental category: during storage according to IEC 60721 | 1K6 (only occasional condensation), 1C2 (no salt mist), 1S2 (sand must not get inside the devices), 1M4 |
| environmental category: during transport according to IEC 60721 | 2K2, 2C1, 2S1, 2M2 (max. fall height 0.3 m) |
| EMC emitted interference | acc. to IEC 60947-4-2: Class A |
|---|
| communication module is supported: PROFINET standard | Yes |
|---|---|
| communication module is supported: PROFINET high-feature | Yes |
| communication module is supported: EtherNet/IP | Yes |
| communication module is supported: Modbus RTU | Yes |
| communication module is supported: Modbus TCP | Yes |
| communication module is supported: PROFIBUS | Yes |
| of circuit breaker usable for Standard Faults: at 460/480 V according to UL | Siemens type: 3VA52, max. 250 A; Iq = 10 kA |
|---|---|
| of circuit breaker usable for Standard Faults: 60/480 V according to UL | Siemens type: 3VA52, max. 250 A; Iq max = 65 kA |
| of circuit breaker usable for Standard Faults: 60/480 V at inside-delta circuit according to UL | Siemens type: 3VA52, max. 250 A; Iq max = 65 kA |
| of circuit breaker usable for Standard Faults: at 575/600 V according to UL | Siemens type: 3VA52, max. 250 A; Iq = 10 kA |
| of circuit breaker usable for Standard Faults: 75/600 V at inside-delta circuit according to UL | Siemens type: 3VA52, max. 250 A; Iq max = 65 kA |
| of the fuse: usable for Standard Faults up to 575/600 V according to UL | Type: Class RK5 / K5, max. 350 A; Iq = 10 kA |
| of the fuse: usable for High Faults up to 575/600 V according to UL | Type: Class J / L, max. 350 A; Iq = 100 kA |
| of the fuse: usable for Standard Faults at inside-delta circuit up to 575/600 V according to UL | Type: Class RK5 / K5, max. 350 A; Iq = 10 kA |
| of the fuse: usable for High Faults at inside-delta circuit up to 575/600 V according to UL | Type: Class J / L, max. 350 A; Iq = 100 kA |
| operating power [hp] for 3-phase motors: at 200/208 V at 50 °C rated value | 30 hp |
| operating power [hp] for 3-phase motors: at 220/230 V at 50 °C rated value | 30 hp |
| operating power [hp] for 3-phase motors: at 460/480 V at 50 °C rated value | 75 hp |
| operating power [hp] for 3-phase motors: at 200/208 V at inside-delta circuit at 50 °C rated value | 50 hp |
| operating power [hp] for 3-phase motors: at 220/230 V at inside-delta circuit at 50 °C rated value | 60 hp |
| operating power [hp] for 3-phase motors: at 460/480 V at inside-delta circuit at 50 °C rated value | 125 hp |
| contact rating of auxiliary contacts according to UL | R300-B300 |
| Safety Integrity Level (SIL) according to IEC 62061 | SIL 1 |
|---|---|
| PFHD with high demand rate according to IEC 62061 | 1E-6 1/h |
| performance level (PL) according to ISO 13849-1 | PL c |
|---|---|
| category according to ISO 13849-1 | 2 |
| Safety Integrity Level (SIL): according to IEC 61508 | SIL 1 |
|---|---|
| safety device type according to IEC 61508-2 | Type B |
| PFHD with high demand rate according to IEC 61508 | 1E-6 1/h |
| PFDavg with low demand rate according to IEC 61508 | 0.09 |
| Safe failure fraction (SFF) | 60 % |
| hardware fault tolerance according to IEC 61508 | 0 |
| T1 value of service life according to IEC 61508 | 20 a |
| protection class IP on the front according to IEC 60529 | IP00; IP20 with cover |
|---|---|
| touch protection on the front according to IEC 60529 | finger-safe, for vertical contact from the front with cover |
| Safety Integrity Level (SIL) according to IEC 61508 relating to ATEX | SIL 1 |
|---|---|
| PFHD with high demand rate according to IEC 61508 relating to ATEX | 5E-7 1/h |
| PFDavg with low demand rate according to IEC 61508 relating to ATEX | 0.008 |
| hardware fault tolerance according to IEC 61508 relating to ATEX | 0 |
| T1 value for proof test interval or service life according to IEC 61508 relating to ATEX | 3 a |
| certificate of suitability: ATEX | Yes |
| certificate of suitability: IECEx | Yes |
| certificate of suitability: according to ATEX directive 2014/34/EU | BVS 18 ATEX F 003 X |
| type of protection according to ATEX directive 2014/34/EU | II (2)G [Ex eb Gb] [Ex db Gb] [Ex pxb Gb], II (2)D [Ex tb Db] [Ex pxb Db], I (M2) [Ex db Mb] |
| Environmental Product Declaration: global warming potential [CO2 eq] / during manufacturing | 92.6 kg |
|---|
| Net weight | 6.509 kg |
|---|---|
| Package dimensions | 396 × 298 × 328 mm |
| Country of origin | CZ |
| Shipping weight | 7.509 kg |
| Ships from | Türkiye |
| Dispatch | — |
| Stock | On request |
Source: manufacturer data · Last verified: 31 Oct 2026
No documents are on file for this part yet.
Ask us for the datasheet| Motor power | Rated current | Part number | Model no | Stock | Dispatch | Price | Add to cart |
|---|---|---|---|---|---|---|---|
| 13 A | 3RW5513-1HF14 | 3RW5 | On request | — | $1,364.76 | Quote | |
| 18 A | 3RW5514-1HF14 | 3RW5 | On request | — | $1,521.77 | Quote | |
| 25 A | 3RW5515-1HF14 | 3RW5 | On request | — | $1,690.87 | Quote | |
| 32 A | 3RW5516-1HF14 | 3RW5 | On request | — | $1,884.09 | Quote | |
| 38 A | 3RW5517-1HF14 | 3RW5 | On request | — | $2,101.49 | Quote | |
| 47 A | 3RW5524-1HF14 | 3RW5 | On request | — | $2,379.25 | Quote | |
| 63 A | 3RW5525-1HF14 | 3RW5 | On request | — | $2,644.97 | Quote | |
| 77 A | 3RW5526-1HF14 | 3RW5 | On request | — | $2,946.85 | Quote | |
| 93 A | 3RW5527-1HF14 | 3RW5 | On request | — | $3,224.69 | Quote | |
| 113 A | 3RW5534-6HF14 This part | 3RW5 | On request | — | $3,623.19 | Quote | |
| 143 A | 3RW5535-6HF14 | 3RW5 | On request | — | $4,323.66 | Quote | |
| 171 A | 3RW5536-6HF14 | 3RW5 | On request | — | $5,024.13 | Quote | |
| 210 A | 3RW5543-6HF14 | 3RW5 | On request | — | $5,857.49 | Quote | |
| 250 A | 3RW5544-6HF14 | 3RW5 | On request | — | $6,835.70 | Quote | |
| 315 A | 3RW5545-6HF14 | 3RW5 | On request | — | $8,103.83 | Quote | |
| 370 A | 3RW5546-6HF14 | 3RW5 | On request | — | $9,480.67 | Quote | |
| 470 A | 3RW5547-6HF14 | 3RW5 | On request | — | $11,171.42 | Quote | |
| 570 A | 3RW5548-6HF14 | 3RW5 | On request | — | $12,560.32 | Quote | |
| 630 A | 3RW5552-6HA14 | 3RW5 | Low stock | $10,435.11 | |||
| 720 A | 3RW5553-6HA14 | 3RW5 | Low stock | $11,579.30 | |||
| 840 A | 3RW5554-6HA14 | 3RW5 | Low stock | $12,481.59 | |||
| 1100 A | 3RW5556-6HA14 | 3RW5 | On request | — | $17,980.27 | Quote | |
| 1280 A | 3RW5558-6HA14 | 3RW5 | On request | — | $20,377.67 | Quote |
The rated current of 3RW55 is 113 A.
The rated operational voltage of 3RW55 is 480 V AC.
The EAN (GTIN) of 3RW55 is 4047621040646.
3RW55 ships from Türkiye. Shipping calculated at checkout · import duties and taxes paid on arrival.
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