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Siemens 3RT1045-3XB40-0LA2 — Contactors

Siemens 3RT1045-3XB40-0LA2 SIRIUS Power Contactor, S3 Size

MPN3RT1045-3XB40-0LA2

Siemens SIRIUS power contactor, S3 size, 3RT1045-3XB40-0LA2, 45 kW at 500 V, screw-type terminals, 70 mm wide.

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

3RT1045-3XB40-0LA2 — Identification
ParameterValue
Contactor frame sizeS3
3RT1045-3XB40-0LA2 — 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
3RT1045-3XB40-0LA2 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RT1045-3XB40-0LA2 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
3RT1045-3XB40-0LA2 — 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
3RT1045-3XB40-0LA2 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Aux. / control circuit connectionspring-loaded terminals
Conductor cross-section, solid2x (0.25 ... 2.5 mm²)
Conductor cross-section, solid or stranded2x (2.5 ... 16 mm²)
Conductor cross-section, finely stranded w/ ferrule2x (0.25 ... 1.5 mm²)
Mounting methodscrew and snap-on mounting onto 35 mm and 75 mm standard mounting rail
Side-by-side mountingYes
3RT1045-3XB40-0LA2 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT1045-3XB40-0LA2 — Environmental
ParameterValue
Operating temperature range-40 ... +70 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT1045-3XB40-0LA2 — Mechanical
ParameterValue
Width70 mm
Height176 mm
Depth152 mm

Product details

The 3RT1045-3XB40-0LA2: This S3-size contactor is rated for motor switching at 45 kW on a 500 V supply and 21.1 kW at 690 V. Those are the AC-3 duty ratings — the ones that govern real motor loads, not the higher AC-1 resistive rating. The 70 mm width and 176 mm height fit a standard 35 mm or 75 mm DIN rail, with screw and snap-on mounting.

Integration Notes

Mounts on 35 mm or 75 mm standard mounting rail via screw and snap-on. Side-by-side mounting is permitted, saving panel width.

Coil and Auxiliary Circuit

The coil is rated 24 V DC, drawing 10 A at the rated value. Switching times: arcing time 10 to 15 ms, DC switching time 14 to 20 ms. Auxiliary contact ratings: 6 A at 230 V, 3 A at 400 V, 1 A at 110 V, 0.3 A at 220 V.

Frequently asked questions

What are the key motor power ratings for this contactor?

The contactor is rated for 45 kW at 500 V and 21.1 kW at 690 V under AC-3 duty, which is the relevant rating for switching standard three-phase induction motors.

What is the physical size and mounting method?

The contactor is 70 mm wide, 176 mm high, 152 mm deep. It mounts on 35 mm or 75 mm standard DIN rail using screw and snap-on fastening. Side-by-side mounting is allowed.

What type of terminals does the main circuit use?

The main current circuit uses screw-type terminals, accepting solid or stranded conductors up to 50 mm².

MPN
3RT1045-3XB40-0LA2