Skip to main content
Siemens 3RT2018-1BF42 — Contactors

Siemens 3RT2018-1BF42 SIRIUS Power Contactor, 110 V coil, Si

MPN3RT2018-1BF42
Active

Siemens SIRIUS 3RT2018-1BF42, Size S00 power contactor, 110 V AC coil, screw-type terminals, 45 mm wide, 30 million mechanical cycles.

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

3RT2018-1BF42 — Identification
ParameterValue
Contactor frame sizeS00
3RT2018-1BF42 — Ratings & Performance
ParameterValue
Rated operational current, AC-12, max.10 A
Rated operational current, AC-4 @ 400 V11.5 A
Rated value @ 400 V3 A
Rated value @ 500 V2 A
Rated value @ 690 V1 A
Rated value @ 230 V2 hp
Rated value @ 24 V10 A
Rated value @ 60 V2 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT2018-1BF42 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RT2018-1BF42 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT2018-1BF42 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusegG: 50A (690V,100kA), aM: 25A (690V,100kA), BS88: 50A (415V,80kA)
Short-circuit coordination type 2, fusegG: 25A (690V,100kA), aM: 20A (690V,100kA), BS88: 25A (415V,80kA)
Aux. switch short-circuit protection, fusegG: 10 A (500 V, 1 kA)
3RT2018-1BF42 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Aux. / control circuit connectionscrew-type terminals
Conductor cross-section, solid0.5 ... 4 mm²
Conductor cross-section, solid or stranded2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), 2x 4 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
3RT2018-1BF42 — Durability
ParameterValue
Durability (operating cycles, typ.)30 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT2018-1BF42 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT2018-1BF42 — Mechanical
ParameterValue
Width45 mm
Height58 mm
Depth73 mm

Product details

The main contacts are rated for 20 A (AC-1) through 12 A (AC-3) — the AC-3 figure is the one that governs motor switching; the AC-1 number applies for resistive loads like heaters. Switching frequency tops out at 750 cycles per hour for AC-3 duty, and 250 for AC-4 (plugging/reversing). If you're cycling a conveyor reverser faster than that, you'll need a larger frame or a dedicated reversing contactor pair. Coil pickup is at 0.8 x rated voltage, dropout at 1.1 x rated voltage. The coil uses screw-type terminals. Auxiliary contacts are present (one N.O. + one N.C. built in), rated for 10 A at 24 V, 2 A at 48/60 V, 1 A at 110 V, and 0.3 A at 220 V. That covers feedback to a PLC input or holding circuit on the coil. Wire range: solid or stranded 0.5 to 4 mm² (20 to 12 AWG), and it accepts two conductors per clamp in certain combinations (2x 0.5-1.5 mm², 2x 0.75-2.5 mm², or 2x 4 mm²). That's handy for daisy-chaining control power without extra terminals.

That's tight enough that you can stack contactors side-by-side on the same DIN rail without extra spacing, as long as you respect the 6 mm side gap. The arcing time is 10-15 ms, and DC dropout is 7-13 ms — fast enough for most interlocking circuits.

Frequently asked questions

What are the clearance requirements around this contactor?

10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm to the side. That allows side-by-side mounting on DIN rail without extra spacing.

MPN
3RT2018-1BF42