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Siemens 3RT1024-1BW40 — Contactors

Siemens 3RT1024-1BW40 SIRIUS Power Contactor, S0 Frame, 48 V

MPN3RT1024-1BW40

Siemens SIRIUS 3RT1024-1BW40 power contactor, S0 frame, 48 VDC coil, screw-type terminals, 45 mm width, IP20 front protection.

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

3RT1024-1BW40 — Identification
ParameterValue
Contactor frame sizeS0
3RT1024-1BW40 — Ratings & Performance
ParameterValue
Rated operational current, AC-4 @ 400 V12.5 A
Rated value @ 400 V3 A
Rated value @ 500 V7.5 kW
Rated value @ 690 V7.5 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
3RT1024-1BW40 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RT1024-1BW40 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT1024-1BW40 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusefuse gL/gG: 63 A
Short-circuit coordination type 2, fusefuse gL/gG: 25 A
Aux. switch short-circuit protection, fusefuse gL/gG: 10 A
3RT1024-1BW40 — Connection & Mounting
ParameterValue
Main 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, finely stranded w/ ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Side-by-side mountingYes
3RT1024-1BW40 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT1024-1BW40 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
3RT1024-1BW40 — Mechanical
ParameterValue
Width45 mm
Height85 mm
Depth101 mm

Product details

It carries a 48 VDC coil and is rated for AC-2 duty at 5.5 kW at 400 V, and AC-4 at 12.5 A at 400 V — the AC-4 figure is the one that governs reversing or plugging duty where the contactor makes and breaks the motor current under load. The DC coil draws 5.4 W on closing and 5.4 W to hold, so the holding power is the same as the inrush — no extra thermal load on the control transformer once it's sealed.

The 48 VDC coil is the main spec that decides fit — if your control voltage is 24 VDC or 110 VDC, this isn't the variant you want. The coil pull-in and dropout thresholds aren't listed here, but the holding power being equal to closing power (5.4 W) means the coil doesn't have a separate economy winding; it's a single-winding DC design. For short-circuit coordination, Type 2 coordination requires a gL/gG fuse rated 25 A, while Type 1 coordination allows up to 63 A. That's the difference between protecting the contactor itself (Type 2) versus just clearing the fault (Type 1).

Panel integration

At 45 mm wide and 85 mm tall, with a 101 mm depth, this S0 contactor fits the standard DIN-rail footprint. Screw-type terminals on the main circuit accept solid or stranded conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), up to max 2x (0.75 to 4 mm²). For AWG, that's 2x (16 to 12), 2x (14 to 10), or 1x 8. The coil terminals are separate and follow the same wire range.

Frequently asked questions

What are the key ratings for this contactor?

The coil is 48 VDC drawing 5.4 W. For motor loads, it's rated 5.5 kW at AC-2 at 400 V, and 12.5 A at AC-4 at 400 V. The DC switching capacity is 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V.

What is the physical size and mounting?

It's an S0 frame: 45 mm wide, 85 mm tall, 101 mm deep. Mounts on 35 mm DIN rail per EN 50022 via screw or snap-on. Side-by-side mounting is allowed with 6 mm clearance.

Can this contactor be used in washdown environments?

No. The front is IP20 (finger-safe), but the terminals are IP00, so it's not rated for moisture or washdown. It belongs inside a closed panel.

MPN
3RT1024-1BW40