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Siemens 3RT2038-3KB40 — Contactors

Siemens 3RT2038-3KB40 SIRIUS coupling contactor, 24 V coil,

MPN3RT2038-3KB40
Active

Siemens SIRIUS Size S2 coupling contactor, 3RT2038-3KB40, 24 VDC coil, spring-cage terminals, 55 mm wide, 130 mm deep, DIN-rail snap-on mounting.

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

3RT2038-3KB40 — Identification
ParameterValue
Contactor frame sizeS2
3RT2038-3KB40 — 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 V2 A
Rated value @ 690 V1 A
Rated value @ 230 V15 hp
Rated value @ 24 V10 A
Rated value @ 60 V2 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT2038-3KB40 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RT2038-3KB40 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT2038-3KB40 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusegG: 250 A (690 V, 100 kA), aM: 160 A (690 V, 100 kA), BS88: 200 A (415 V, 80 kA)
Short-circuit coordination type 2, fusegG: 160A (690V,100kA), aM: 80A (690V,100kA), BS88: 125A (415V,80kA)
Aux. switch short-circuit protection, fusegG: 10 A (500 V, 1 kA)
3RT2038-3KB40 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Aux. / control circuit connectionspring-loaded terminals
Conductor cross-section, solid or stranded2x (0.5 ... 2.5 mm²)
Conductor cross-section, finely stranded w/ ferrule2x (0.5 ... 1.5 mm²)
Mounting methodscrew and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715
Side-by-side mountingYes
3RT2038-3KB40 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT2038-3KB40 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT2038-3KB40 — Mechanical
ParameterValue
Width55 mm
Height114 mm
Depth130 mm

Product details

Coupling contactor, Size S2 — 24 V coil, spring-cage terminals

The 3RT2038-3KB40 is a Siemens SIRIUS Size S2 coupling contactor. It carries a 24 V rated coil with a 10 A switching capacity at that voltage. The contactor uses spring-cage terminals on the main contacts, accepting 2x (0.5... 2.5 mm²) solid or stranded wire.

Switching performance and mechanical life

The AC-1 resistive load curve supports up to 700 ops/h. Mechanical life typical is 10,000,000 operations. Arcing time runs 10...20 ms; DC switching times are 30...55 ms. Auxiliary switch block is included. The contactor carries a 1.2 full-scale factor and 0.8 initial value — derate accordingly for inductive loads.

Frequently asked questions

What are the key dimensions of 3RT2038-3KB40?

Width is 55 mm, height is 114 mm, depth is 130 mm. It mounts on 35 mm DIN rail per DIN EN 60715.

What type of coil and terminals does this contactor use?

The coil is rated 24 V with a 10 A switching capacity at that voltage. Main contacts use spring-cage terminals accepting 2x (0.5 to 2.5 mm²) solid or stranded wire.

MPN
3RT2038-3KB40