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Siemens 3RT2018-2AN21 — Contactors

Siemens 3RT2018-2AN21 SIRIUS Power Contactor, Size S00, 24 V

MPN3RT2018-2AN21
Active

Siemens SIRIUS power contactor, Size S00, 24 VDC coil, spring-type terminals, 3RT2018-2AN21.

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

3RT2018-2AN21 — Identification
ParameterValue
Contactor frame sizeS00
3RT2018-2AN21 — 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
3RT2018-2AN21 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.25
Rated value @ 50 Hz220 V
3RT2018-2AN21 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT2018-2AN21 — 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)
3RT2018-2AN21 — Connection & Mounting
ParameterValue
Main circuit connectionspring-loaded terminals
Aux. / control circuit connectionspring-loaded terminals
Conductor cross-section, solid0.5 ... 4 mm²
Conductor cross-section, solid or stranded2x (0,5 ... 4 mm²)
Conductor cross-section, finely stranded w/ ferrule2x (0.5 ... 2.5 mm²)
Mounting methodscrew and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715
Side-by-side mountingYes
3RT2018-2AN21 — Durability
ParameterValue
Durability (operating cycles, typ.)30 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT2018-2AN21 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT2018-2AN21 — Mechanical
ParameterValue
Width45 mm
Height70 mm
Depth73 mm
3RT2018-2AN21 — Specifications
ParameterValue
At AC4 ... 15 ms

Product details

The 24 VDC coil pulls in at nominal voltage and holds reliably across the -25 to +60 °C operating range. Coil terminals are spring-type (push-in), which speeds wiring compared to screw terminals — strip 8 mm, push, done.

Size S00 means the contactor body is 70 mm tall, 45 mm wide, and 73 mm deep — compact enough to pack several units side-by-side on a DIN rail. The 45 mm width is a single modular unit (1 MW = 18 mm), so it occupies 2.5 MW of rail space. That matters when you're laying out a dense panel and every millimeter of DIN rail is spoken for. Switching frequency varies by duty class: up to 1,000 cycles/hour for AC-1 resistive loads, 750 cycles/hour for AC-2 and AC-3 motor loads, and 250 cycles/hour for AC-4 (plugging/inching). If your application cycles a motor on/off every few seconds, the AC-3 ceiling of 750 ops/hour (one cycle every 4.8 seconds) is the hard limit — exceed it and the contactor overheats. The auxiliary switch is built in (1 NO + 1 NC, 20...12 on the main contact scale), which saves buying a separate side-mount block for basic feedback. For higher auxiliary contact counts, you add a SIRIUS auxiliary switch block that clips onto the front.

That means it fits in panels where the DIN rail is mounted sideways or at an angle — common in tight retrofit enclosures.

Wire range: solid or stranded 0.5...4 mm², with two conductors per terminal possible (2x 0.5...4 mm²). The spring terminals accept ferruled stranded wire cleanly. That 6 mm side gap is tight — if you're mounting contactors side-by-side, they can touch; the gap is for air circulation, not electrical clearance.

Frequently asked questions

What is the depth of 3RT2018-2AN21?

The depth is 73 mm. Overall dimensions are 70 mm height, 45 mm width, and 73 mm depth.

What wire sizes does the spring terminal accept?

Solid or stranded wire from 0.5 to 4 mm², and two conductors of the same range per terminal (2x 0.5...4 mm²).

Where can I buy 3RT2018-2AN21?

This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time.

Will 3RT2018-2AN21 fit in a panel designed for 3RT2015-2AP01?

Both are Size S00 contactors with the same 45 mm width and DIN rail mounting, so the footprint is identical. The main difference is the coil voltage — 3RT2018-2AN21 uses 24 VDC, while 3RT2015-2AP01 uses a different coil. Check the coil voltage matches your control circuit before swapping.

MPN
3RT2018-2AN21