Skip to main content
Siemens 3RT2027-1BB44 — Contactors

Siemens SIRIUS 3RT2027-1BB44 Power Contactor, S0, 24 VDC Coi

MPN3RT2027-1BB44
Active

Siemens SIRIUS 3RT2027-1BB44 power contactor, size S0, 24 VDC coil, screw-type terminals, 3-pole main contacts, 45 mm width.

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

3RT2027-1BB44 — Identification
ParameterValue
Contactor frame sizeS0
3RT2027-1BB44 — 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 V6 A
Rated value @ 60 V2 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT2027-1BB44 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RT2027-1BB44 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT2027-1BB44 — 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)
3RT2027-1BB44 — 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
3RT2027-1BB44 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT2027-1BB44 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT2027-1BB44 — Mechanical
ParameterValue
Width45 mm
Height85 mm
Depth151 mm

Product details

The 3RT2027-1BB44: The 24 VDC coil draws 6 A at its rated value, which is the inrush current to pull the armature in. The coil operating range is 0.8 to 1.1 times the rated voltage, so it will pick up reliably at 19.2 VDC and hold in up to 26.4 VDC. This is a standard control voltage for industrial DC buses, common in PLC-driven panels. The main contacts are rated for AC-3 duty (squirrel-cage motor switching) at 750 operating cycles per hour maximum, and AC-1 (resistive) at 1,000 cycles per hour. For the most demanding AC-4 duty (inching/plugging), the maximum is 250 cycles per hour. These limits govern the thermal load on the contact tips — exceeding them accelerates wear, especially on AC-4 where the contacts make and break under full motor current. For DC switching, the contactor is rated at 6 A at 24 V, 2 A at 48 V and 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, and 3 A at 400 V. These are the maximum resistive currents the contacts can interrupt at those voltages — DC arcs are harder to extinguish than AC, so the ratings drop sharply as voltage rises. The motor rating at 230 V is 5 hp, which gives a quick sizing reference for typical North American motor loads on a 230 V single-phase or three-phase supply.

This allows installation in tight or awkward panel orientations without derating. Physical dimensions are 85 mm height, 45 mm width, and 151 mm depth. These are minimum air gaps for arc flash and heat dissipation — crowding the contactor reduces its effective switching life. Wire range for the main and coil terminals: solid or stranded 1 to 10 mm², or two conductors of 0.5 to 1.5 mm² or 0.75 to 2.5 mm². The screw-type terminals are standard for panel wiring — no special crimp tools needed, but torque to the manufacturer's specification (not listed here) for reliable connection.

Operating Conditions and Lifecycle

The operating temperature range covers most indoor industrial environments; the wide storage range allows for unheated warehouses or shipping in extreme climates. The dropout delay is the time from coil power removal to main contact opening — important for sequencing in safety circuits or when coordinating with upstream breakers.

Configuration Notes

This variant has no auxiliary switch block integrated — the auxiliary switch is listed as 'No'. If you need auxiliary contacts for status feedback or interlocking, you will need to order a separate auxiliary contact block (e.g., the 3RT29 series) that clips onto the front or side of the S0 contactor. The main contact configuration is listed as '16... 8', which typically indicates the contact arrangement for a 3-pole contactor with normally open main contacts. This is the standard for motor starting — three NO poles for the motor circuit.

Frequently asked questions

What compliance documentation is available for the 3RT2027-1BB44?

As a Siemens SIRIUS product, it is manufactured under IEC and EN standards (the DIN rail mounting references DIN EN 60715). Typical compliance includes CE marking for the European market, and UL/CSA listings for North America (though specific certification numbers are not in this record). The product is RoHS and REACH compliant as standard for current Siemens industrial control gear. For specific certificates, the Siemens Industry Online Support portal provides the declaration of conformity and UL file number under the 3RT2 series.

MPN
3RT2027-1BB44