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Siemens 3RT1023-1AU00 — Contactors

Siemens 3RT1023-1AU00 SIRIUS Power Contactor, S0, 4.5 kW at

MPN3RT1023-1AU00

Siemens SIRIUS power contactor, size S0, 3-pole, 4.5 kW at 500 V, 5.5 kW at 690 V, screw terminals, 45 mm wide.

Source DocumentedChannel stated on listing & quote
Condition PhotosReal unit photos / video on request
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Worldwide DispatchDHL/FedEx — transit quoted per order
Independent China distributor & sourcing agent· Listing updated Sep 2026

Specifications

3RT1023-1AU00 — Identification
ParameterValue
Contactor frame sizeS0
3RT1023-1AU00 — Ratings & Performance
ParameterValue
Rated operational current, AC-4 @ 400 V8.5 A
Rated value @ 400 V3 A
Rated value @ 500 V4.5 kW
Rated value @ 690 V5.5 kW
Rated value @ 230 V6 A
Rated value @ 24 V10 A
Rated value @ 60 V2 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT1023-1AU00 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.8 ... 1.1
Rated value @ 50 Hz240 V
3RT1023-1AU00 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT1023-1AU00 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusefuse gL/gG: 63 A
Short-circuit coordination type 2, fusefuse gL/gG: 25 A
Aux. switch short-circuit protection, fusefuse gL/gG: 10 A
3RT1023-1AU00 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Conductor cross-section, solid2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 mm²)
Conductor cross-section, finely stranded w/ ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Side-by-side mountingYes
3RT1023-1AU00 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT1023-1AU00 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
3RT1023-1AU00 — Mechanical
ParameterValue
Width45 mm
Height85 mm
Depth91 mm

Product details

It carries 4.5 kW at 500 V and 5.5 kW at 690 V in AC-3 duty, which is the standard motor-switching category — meaning it handles the inrush and breaking of induction motors at those power levels without welding the contacts. The 3-pole main contact block has 3 normally-open contacts and no normally-closed contacts, so it's a straight motor starter contactor, not a reversing or star-delta configuration.

The 45 mm width means it occupies one standard modular unit, so it fits neatly into a row of motor starters or alongside a thermal overload relay. The front face carries an IP20 rating — safe for finger contact in an enclosure — while the terminals themselves are IP00, meaning they rely on the panel's own protection. Side-by-side mounting is allowed with no derating gap, so you can pack multiple contactors tight on the rail.

Main circuit terminals are screw-type, accepting solid conductors: 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or max 2x 0.75–4 mm². For stranded wire, the range is 2x 1–2.5 mm², 2x 2.5–6 mm², or max 2x 10 mm². AWG equivalents are 2x 16–12, 2x 14–10, and 1x 8. This covers most panel wiring from control circuits up to moderate motor feeders. The pollution degree is 3 (conductive or dry non-conductive pollution), typical for industrial environments.

Coil and auxiliary ratings

The coil is rated for 50 Hz at 240 V, with an operating range of 0.8 to 1.1 times the rated voltage at 50 Hz. That means it picks up reliably down to about 192 V and holds in up to 264 V. For auxiliary contacts (not built-in, but add-on blocks are available), the rated currents at various voltages are: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V.

Short-circuit protection and coordination

For Type 1 coordination (contactor may need replacement after a fault), the fuse can be gL/gG 63 A. This lets you balance protection level against fuse size depending on the panel's selectivity requirements.

Frequently asked questions

What are the key motor ratings for this contactor?

It is rated for 4.5 kW at 500 V and 5.5 kW at 690 V in AC-3 duty. The AC-4 (plugging/inching) current rating is 8.5 A at 400 V.

What is the physical size and mounting of the 3RT1023-1AU00?

It is 45 mm wide, 85 mm high, and 91 mm deep. It mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022.

What wire sizes does the screw terminal accept?

For solid wire: 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², max 2x 0.75–4 mm². For stranded: 2x 1–2.5 mm², 2x 2.5–6 mm², max 2x 10 mm². AWG equivalents: 2x 16–12, 2x 14–10, 1x 8.

What is the closest functional alternative to the 3RT1023-1AU00?

The 3RT1023-1AL20 is a sibling in the same S0 frame size and SIRIUS family. The main difference is the coil voltage — the -1AL20 uses a 24 V AC/DC coil, while the -1AU00 uses a 240 V 50 Hz coil. They share the same power ratings, terminal layout, and mounting footprint, so swapping one for the other requires only a coil voltage change in the panel design.

MPN
3RT1023-1AU00