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Siemens 3RT2027-1AU20 — Contactors

Siemens 3RT2027-1AU20 SIRIUS Power Contactor, S0 Frame, 24 V

MPN3RT2027-1AU20
Active

Siemens SIRIUS power contactor, 3RT2027-1AU20, S0 frame, 24 VAC 50/60 Hz coil, screw-type terminals, 45 mm wide, for DIN rail 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

3RT2027-1AU20 — Identification
ParameterValue
Contactor frame sizeS0
3RT2027-1AU20 — Ratings & Performance
ParameterValue
Rated operational current, AC-12, max.10 A
Rated operational current, AC-4 @ 400 V22 A
Rated value @ 400 V3 A
Rated value @ 500 V2 A
Rated value @ 690 V1 A
Rated value @ 230 V5 hp
Rated value @ 24 V10 A
Rated value @ 60 V2 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT2027-1AU20 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.25
Rated value @ 50 Hz380 V
3RT2027-1AU20 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT2027-1AU20 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusegG: 125A (690V,100kA), aM: 50A (690V,100kA), BS88: 125A (415V,80kA)
Short-circuit coordination type 2, fusegG: 50A (690V,100kA), aM: 25A (690V, 100kA), BS88: 50A (415V, 80kA)
Aux. switch short-circuit protection, fusegG: 10 A (500 V, 1 kA)
3RT2027-1AU20 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Aux. / control circuit connectionscrew-type terminals
Conductor cross-section, solid1 ... 10 mm²
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 DIN rail according to DIN EN 60715
Side-by-side mountingYes
3RT2027-1AU20 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT2027-1AU20 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT2027-1AU20 — Mechanical
ParameterValue
Width45 mm
Height85 mm
Depth97 mm
3RT2027-1AU20 — Specifications
ParameterValue
At AC4 ... 16 ms

Product details

What It Is & Where It Goes

The 24 VAC 50/60 Hz coil draws 0.25 A at 50 Hz and 0.28 A at 60 Hz — a standard control voltage that matches most PLC or relay outputs in European and North American panels.

The 45 mm width and 85 mm height fit standard S0 contactor spacing in a panel.

Switching Performance & Duty Cycles

Rated for 1 000 000 electrical operations typical. Maximum switching frequency varies by duty: 1 000 cycles/hour for AC-1 (resistive), 750 cycles/hour for AC-2 and AC-3 (motor starting/running), and 250 cycles/hour for AC-4 (plugging/inching). Arcing time is 10 ms. For a bottling line or conveyor running at moderate start frequency, the AC-3 rating of 750 cycles/hour is the relevant limit — it means the contactor can handle a start every ~5 seconds without overheating the arc chamber.

Auxiliary & Main Contact Configuration

Includes an auxiliary switch block. Main contacts accept wire sizes 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²). The S0 frame matches the 3RT2027-1AP60 for mechanical fit.

Frequently asked questions

What is the depth dimension?

The depth is 97 mm. This is the dimension from the DIN rail mounting surface to the front of the contactor, including the arc chamber and terminals.

What wire sizes does the coil terminal accept?

The screw-type coil terminals accept solid or stranded wire from 1 to 10 mm². For the main contact control circuit, it accepts 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²).

What compliance documentation is available?

As a Siemens SIRIUS product, the 3RT2027-1AU20 carries CE marking for the European market and is designed to meet IEC/EN 60947-4-1. RoHS and REACH compliance declarations are standard from Siemens. UL and CSA listings are typical for this series, though the specific certification numbers should be confirmed against the nameplate on the unit you receive.

MPN
3RT2027-1AU20