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Siemens 3RT1044-1AC20 — Contactors

Siemens 3RT1044-1AC20 SIRIUS Power Contactor, Size S3, 70 mm

MPN3RT1044-1AC20

Siemens SIRIUS power contactor, size S3, 3RT1044-1AC20, 70 mm width, screw-type terminals, IP20 front, snap-on 35/75 mm rail.

Source DocumentedChannel stated on listing & quote
Condition PhotosReal unit photos / video on request
WhatsApp AnswersFast human replies for machine-down parts
Worldwide DispatchDHL/FedEx — transit quoted per order
Independent China distributor & sourcing agent· Listing updated Sep 2026

Specifications

3RT1044-1AC20 — Identification
ParameterValue
Contactor frame sizeS3
3RT1044-1AC20 — Ratings & Performance
ParameterValue
Rated operational current, AC-12, max.10 A
Rated operational current, AC-4 @ 400 V55 A
Rated value @ 400 V3 A
Rated value @ 500 V37 kW
Rated value @ 690 V18.6 kW
Rated value @ 230 V6 A
Rated value @ 24 V10 A
Rated value @ 60 V2 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT1044-1AC20 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.8 ... 1.1
Rated value @ 50 Hz24 V
3RT1044-1AC20 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT1044-1AC20 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusefuse gL/gG: 250 A
Short-circuit coordination type 2, fusefuse gL/gG: 125 A
Aux. switch short-circuit protection, fusefuse gL/gG: 10 A
3RT1044-1AC20 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Aux. / control circuit connectionscrew-type terminals
Conductor cross-section, solid2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 mm²)
Conductor cross-section, solid or stranded2x (2.5 ... 16 mm²)
Conductor cross-section, finely stranded w/ ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Mounting methodscrew and snap-on mounting onto 35 mm and 75 mm standard mounting rail
Side-by-side mountingYes
3RT1044-1AC20 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT1044-1AC20 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT1044-1AC20 — Mechanical
ParameterValue
Width70 mm
Height146 mm
Depth139 mm
3RT1044-1AC20 — Specifications
ParameterValue
At AC10 ... 19 ms

Product details

It mounts on 35 mm or 75 mm standard mounting rail via screw or snap-on fastening, and its 70 mm width fits alongside other SIRIUS components without extra spacing — side-by-side mounting is supported.

Pollution degree 3 means it tolerates conductive dust and humidity typical of factory floors — no need for a sealed enclosure unless washdown is present. That's enough for the main power feed on a size S3 contactor — typical for motor circuits up to around 37 kW at 500 V or 18.6 kW at 690 V.

Frequently asked questions

What are the mounting dimensions?

Width is 70 mm, height 146 mm, depth 139 mm. It snaps onto 35 mm or 75 mm standard mounting rail.

What wire sizes does the main circuit accept?

Solid: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), max 2x (0.75 to 4 mm²). Stranded: 2x (10 to 50 mm²).

What compliance documentation is available?

The part carries Siemens SIRIUS branding with standard CE/UL/CSA markings typical for the series. Specific RoHS/REACH declarations are available from Siemens documentation resources.

MPN
3RT1044-1AC20