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Siemens 3RT5045-1AG20 — Contactors

Siemens 3RT5045-1AG20 SIRIUS Power Contactor, S3, 70 mm

MPN3RT5045-1AG20

Siemens SIRIUS power contactor, Size S3, order code 3RT5045-1AG20, screw-type terminals, 70 mm width, 146 mm height, 139 mm depth, rated for motor loads up to 38 kW at 230 V and 66 kW at 400 V at 60 °C.

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

3RT5045-1AG20 — Identification
ParameterValue
Contactor frame sizeS3
3RT5045-1AG20 — Ratings & Performance
ParameterValue
Rated operational current, AC-12, max.10 A
Rated value @ 400 V3 A
Rated value @ 690 V21.1 kW
Rated value @ 230 V6 A
Rated value @ 24 V6 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT5045-1AG20 — Control & Coil
ParameterValue
Control supply voltage typeAC
Rated value @ 50 Hz0.29
Rated value @ 50 Hz110 V
3RT5045-1AG20 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT5045-1AG20 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusefuse gL/gG: 250 A
Short-circuit coordination type 2, fusefuse gL/gG: 160 A
Aux. switch short-circuit protection, fusefuse gL/gG: 10 A
3RT5045-1AG20 — Connection & Mounting
ParameterValue
Main circuit connectionscrew-type terminals
Aux. / control circuit connectionscrew-type terminals
Conductor cross-section, solid or stranded2x (2.5 ... 16 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 and 75 mm DIN rail
Side-by-side mountingYes
3RT5045-1AG20 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT5045-1AG20 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT5045-1AG20 — Mechanical
ParameterValue
Width70 mm
Height146 mm
Depth139 mm
3RT5045-1AG20 — Specifications
ParameterValue
At AC5 000 1/h

Product details

At 60 °C ambient, it is rated for 38 kW at 230 V and 66 kW at 400 V, with a 690 V rating of 114 kW — these are the motor power ratings that govern real-world sizing, not the lower-temperature figures. The contactor handles up to 1 000 switching cycles per hour in AC-3 duty (AC-3e maximum), matching typical conveyor and pump cycling rates. Operating temperature spans -25 to +60 °C, storage -55 to +80 °C, and the insulation voltage is rated 1 000 V.

RoHS compliance is dated to March 1, 2017, covering the EU substance restrictions. The part carries the SIRIUS brand and is backed by Siemens' standard documentation package (declaration of conformity, UL/CSA/CE certifications available on request).

Mounts on 35 mm or 75 mm DIN rail with screw or snap-on fastening. The 70 mm width and 146 mm height leave room for auxiliary contact blocks alongside. Main circuit terminals accept 2x (2.5... 16 mm²) solid or stranded copper, or 2x (10... 1/0) AWG.

Coil and auxiliary ratings

The coil draws 6 A at 24 V rated value, 1 A at 110 V, and 0.3 A at 220 V — these are the pick-up/hold currents for the control circuit, not the main contact ratings. At 50/60 Hz the coil impedance is 0.29 per the spec, consistent with a standard AC-operated solenoid. Mechanical endurance is 10 000 000 operating cycles typical, with electrical endurance varying by duty: AC-1 (resistive) up to 900 cycles/hour, AC-3 (motor) up to 1 000 cycles/hour, AC-4 (plugging/inching) up to 300 cycles/hour. The 5 000 cycles/hour figure at AC refers to the no-load mechanical rate.

Frequently asked questions

Does 3RT5045-1AG20 drop into a panel built for 3RT5045-1AF00?

Both are Size S3 contactors with the same 70 mm width and screw-type terminals, so the mechanical footprint and wiring interface are identical. The 1AG20 variant carries a different coil voltage or auxiliary configuration — verify the coil rating against your control voltage before swapping.

MPN
3RT5045-1AG20