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Siemens 3RT7027-1AC25 — Contactors

Siemens 3RT7027-1AC25 SIRIUS Contactor, 3-pole AC-3, 24V 50/

MPN3RT7027-1AC25

Siemens SIRIUS 3RT7027-1AC25, size S0 contactor, 3-pole main contacts, AC-3 rated, 24 V AC 50/60 Hz coil, screw-type terminals, IP20 finger-safe.

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

3RT7027-1AC25 — Identification
ParameterValue
Contactor frame sizeS0
3RT7027-1AC25 — Ratings & Performance
ParameterValue
Rated value @ 400 V3 A
Rated value @ 690 V1 A
Rated value @ 230 V6 A
3RT7027-1AC25 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.24
Rated value @ 50 Hz24 V
3RT7027-1AC25 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliabilityacceptability for PLC control (17 V, 5 mA)
3RT7027-1AC25 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusegL/gG NH 3NA: 125 A
Short-circuit coordination type 2, fusegL/gG NH 3NA: 50 A
Aux. switch short-circuit protection, fusefuse gL/gG: 10 A
3RT7027-1AC25 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Aux. / control circuit connectionscrew-type terminals
Conductor cross-section, solid or stranded2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 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 standard mounting rail according to DIN EN 50022
Side-by-side mountingYes
3RT7027-1AC25 — Environmental
ParameterValue
Operating temperature range-10 ... +55 °C
Storage temperature range-25 ... +70 °C
Installation altitude, max.2 000 m
3RT7027-1AC25 — Mechanical
ParameterValue
Width55 mm
Height85.5 mm
Depth91 mm

Product details

It carries three normally-open main contacts (3 NO) rated for AC-3 duty up to 690 V, with a 24 V AC coil that works on both 50 Hz and 60 Hz supplies. This is the standard screw-terminal variant — no auxiliary contacts built in, but the design accepts add-on auxiliary switch blocks when you need them.

The 690 V maximum operating voltage means it's fine on 400 V and 480 V systems, and the insulation voltage is also rated at 690 V (pollution degree 3), so it's suited for industrial environments where conductive dust or condensation is present. The coil holds at 24 V AC nominal, with a closing power draw of 0.72 W and a holding power of just 0.24 W — that's low enough to keep the control transformer small and the heat inside the panel manageable. Mechanical life is solid: the contactor is rated for 800 switching operations per hour at AC-3 maximum, and 250 per hour at AC-4 (plugging/inching duty). That's typical for a size S0 — it'll handle a conveyor start-stop cycle all day, but don't hammer it with reversing starts every few seconds without checking the thermal curve.

Installation notes from the field

They accept 2x (0.5 to 1.5 mm²) solid or stranded, or 2x (0.75 to 2.5 mm²) with ferrules. That's enough for standard motor leads up to about 2.5 mm² — if you're running larger cable, step up to the next frame size or use a terminal block in between. That helps when you're squeezing it into a crowded panel or aligning it with existing busbars. The operating temperature range is -10 to +55 °C, storage from -25 to +70 °C — fine for most indoor panel environments.

Frequently asked questions

What are the key ratings for this contactor?

It is a 3-pole size S0 contactor with a 24 V AC coil (50/60 Hz), rated for AC-3 motor switching up to 690 V. The insulation voltage is 690 V, pollution degree 3, and it has IP20 finger-safe protection on the front and terminals.

What is the mounting method for this contactor?

It uses screw and snap-on mounting onto a 35 mm standard mounting rail per DIN EN 50022. Side-by-side mounting is allowed, and the mounting position can be rotated ±180° on a vertical surface or tilted ±22.5°.

MPN
3RT7027-1AC25