Siemens SIRIUS 3RT2018-2FB42 is a size S00 power contactor with a 24 V DC coil and spring-type terminals that accept 0.5–4 mm² solid or stranded wire. The integrated auxiliary switch carries 10 A at 24 V — enough to feed a PLC input or BMS digital point directly, no separate interface relay needed. Rated for AC-3 duty at 750 switching cycles per hour, with a mechanical life of 30 million operations. Mounts on 35 mm DIN rail via screw or snap-on. Leave 10 mm clearance above and below, 6 mm at the sides. Operates from −25 to +60 °C and stores from −55 to +80 °C.
Siemens 3RT2018-2FB42 SIRIUS Contactor, 24 VDC Spring Termin
MPN3RT2018-2FB42
Active
Siemens SIRIUS 3RT2018-2FB42, size S00 power contactor, 24 VDC coil, spring-type terminals.
$45.72Ref. price · indicative, final on quote
StockContact for availability
MOQ1 pcs
Sourced new & surplus through independent channelsListing updated Jun 2026
Specifications
Identification
| Parameter | Value |
|---|---|
| Contactor frame size | S00 |
Ratings & Performance
| Parameter | Value |
|---|---|
| Rated operational current, AC-12, max. | 10 A |
| Rated operational current, AC-4 @ 400 V | 11.5 A |
| Rated value @ 400 V | 3 A |
| Rated value @ 500 V | 2 A |
| Rated value @ 690 V | 1 A |
| Rated value @ 230 V | 2 hp |
| Rated value @ 24 V | 10 A |
| Rated value @ 60 V | 2 A |
| Rated value @ 110 V | 1 A |
| Rated value @ 220 V | 0.3 A |
Control & Coil
| Parameter | Value |
|---|---|
| Control supply voltage type | DC |
Contacts & Poles
| Parameter | Value |
|---|---|
| Main poles | 3 |
| Main NO contacts | 3 |
| Auxiliary contact reliability | 1 faulty switching per 100 million (17 V, 1 mA) |
Protection & Coordination
| Parameter | Value |
|---|---|
| Short-circuit coordination type 1, fuse | gG: 50A (690V,100kA), aM: 25A (690V,100kA), BS88: 50A (415V,80kA) |
| Short-circuit coordination type 2, fuse | gG: 25A (690V,100kA), aM: 20A (690V,100kA), BS88: 25A (415V,80kA) |
| Aux. switch short-circuit protection, fuse | gG: 10 A (500 V, 1 kA) |
Connection & Mounting
| Parameter | Value |
|---|---|
| Main circuit connection | spring-loaded terminals |
| Aux. / control circuit connection | spring-loaded terminals |
| Conductor cross-section, solid | 0.5 ... 4 mm² |
| Conductor cross-section, solid or stranded | 2x (0,5 ... 4 mm²) |
| Conductor cross-section, finely stranded w/ ferrule | 2x (0.5 ... 2.5 mm²) |
| Mounting method | screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715 |
| Side-by-side mounting | Yes |
Durability
| Parameter | Value |
|---|---|
| Durability (operating cycles, typ.) | 30 000 000 |
| Durability with aux. switch block (cycles, typ.) | 10 000 000 |
Environmental
| Parameter | Value |
|---|---|
| Operating temperature range | -25 ... +60 °C |
| Storage temperature range | -55 ... +80 °C |
| Installation altitude, max. | 2 000 m |
Mechanical
| Parameter | Value |
|---|---|
| Width | 45 mm |
| Height | 70 mm |
| Depth | 73 mm |
Product details
Frequently asked questions
What is the depth of the 3RT2018-2FB42?
73 mm.
What wire sizes does the spring terminal accept for solid conductors?
Solid conductors from 0.5 to 4 mm².
MPN
3RT2018-2FB42