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Siemens 3RT1045-1AH04 — Contactors

Siemens 3RT1045-1AH04 SIRIUS Power Contactor, 45 kW at 500 V

MPN3RT1045-1AH04

Siemens SIRIUS 3RT1045-1AH04 power contactor, size S3, screw-type terminals, 45 kW at 500 V AC-3, 21.1 kW at 690 V AC-3, 66 A at AC-4 400 V, screw and snap-on mounting onto 35 mm and 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

3RT1045-1AH04 — Identification
ParameterValue
Contactor frame sizeS3
3RT1045-1AH04 — Ratings & Performance
ParameterValue
Rated operational current, AC-12, max.10 A
Rated operational current, AC-4 @ 400 V66 A
Rated value @ 400 V3 A
Rated value @ 500 V45 kW
Rated value @ 690 V21.1 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
3RT1045-1AH04 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.8 ... 1.1
Rated value @ 50 Hz48 V
3RT1045-1AH04 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT1045-1AH04 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusefuse gL/gG: 250 A
Short-circuit coordination type 2, fusefuse gL/gG: 160 A
Aux. switch short-circuit protection, fusefuse gL/gG: 10 A
3RT1045-1AH04 — 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
3RT1045-1AH04 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT1045-1AH04 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT1045-1AH04 — Mechanical
ParameterValue
Width70 mm
Height146 mm
Depth188 mm
3RT1045-1AH04 — Specifications
ParameterValue
At AC10 ... 25 ms

Product details

SIRIUS 3RT1045-1AH04: Integrator's Spec Recap

It carries a 45 kW rating at 500 V AC-3 and 21.1 kW at 690 V AC-3 — those are the numbers that decide fit for a given motor. Coil draw at 24 V rated value is 10 A — that's the inrush, not the hold. At 230 V the inrush drops to 6 A, and at 400 V to 3 A. The contactor is rated for 50 Hz operation with an operating range of 0.8 to 1.1 times the rated voltage.

RoHS compliance is indicated by a substance prohibitance date of 05/01/2012, which aligns with the EU RoHS directive. The part carries IP20 on the front with a cover or box terminal; the terminal body itself is IP00, so the panel enclosure provides the overall ingress protection.

Environmental & Mounting Notes

Mechanical life of the contactor typical is 10 million operations. Switching frequency limits: AC-1 maximum 900 cycles per hour, AC-2 maximum 400, AC-3 maximum 1000, AC-4 maximum 300. AC-4 is the limiting factor for heavy-duty reversing.

Frequently asked questions

What are the key ratings for the 3RT1045-1AH04?

The contactor is rated 45 kW at 500 V AC-3, 21.1 kW at 690 V AC-3, and 66 A at AC-4 400 V. Coil inrush at 24 V is 10 A, at 230 V is 6 A, and at 400 V is 3 A.

What mounting options does the 3RT1045-1AH04 support?

It mounts via screw and snap-on onto 35 mm or 75 mm standard DIN rail. Side-by-side mounting is permitted.

What compliance documentation is available for the 3RT1045-1AH04?

RoHS compliance is indicated by a substance prohibitance date of 05/01/2012. The part has IP20 on the front with cover or box terminal, and the terminal body is IP00.

MPN
3RT1045-1AH04