Skip to main content
Log in
Siemens 3RT1023-1AL20 — Contactors

Siemens SIRIUS 3RT1023-1AL20 Power Contactor, S0, 4 kW AC-2

MPN3RT1023-1AL20

Siemens SIRIUS power contactor, size S0, 3RT1023-1AL20, 4 kW at AC-2 400 V, 8.5 A AC-4, screw-type terminals, 45 mm wide, snap-on DIN rail.

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

3RT1023-1AL20 — Identification
ParameterValue
Contactor frame sizeS0
3RT1023-1AL20 — 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
3RT1023-1AL20 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.8 ... 1.1
Rated value @ 50 Hz230 V
3RT1023-1AL20 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT1023-1AL20 — 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
3RT1023-1AL20 — 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
3RT1023-1AL20 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT1023-1AL20 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
3RT1023-1AL20 — Mechanical
ParameterValue
Width45 mm
Height85 mm
Depth91 mm

Product details

The Siemens SIRIUS 3RT1023-1AL20 is a size S0 power contactor rated for switching motor loads in AC-2 duty at 4 kW at 400 V, and carries an AC-4 rating of 8.5 A for reversing or inching applications.

The AC-4 rating of 8.5 A tells you the maximum current it can interrupt during plugging or jogging cycles, which is the more demanding duty for reversing starters. For auxiliary contacts, the 24 V DC rating of 10 A is the one to watch when piloting PLC outputs or relay coils in the same panel. Type 2 coordination (no-weld) requires a gL/gG fuse of 25 A; Type 1 coordination (allow contact weld) allows up to 63 A. This matters for selectivity studies and SCCR compliance in the panel.

Frequently asked questions

What is the closest functional second-source to 3RT1023-1AL20?

The 3RT1017-1AP01 is a smaller-frame SIRIUS contactor but does not match the S0 frame size or the AC-2/AC-4 ratings of this part. For a direct drop-in replacement on the same BOM line, stick with the 3RT1023-1AL20.

Will 3RT1023-1AL20 drop into a panel specified around 3RT1017-1AP01 without rewiring?

No — the 3RT1023-1AL20 is size S0 (45 mm wide) while the 3RT1017-1AP01 is a smaller frame. The mounting footprint and terminal spacing differ, so rewiring and possibly re-drilling the DIN rail mounting holes would be needed.

MPN
3RT1023-1AL20