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Siemens 3RV2421-4AA20 — Motor Protection Circuit Breakers (MPCB)

Siemens 3RV2421-4AA20 SIRIUS Circuit Breaker, Class 10, 100

MPN3RV2421-4AA20
Active

Siemens SIRIUS 3RV2421-4AA20 circuit breaker, transformer protection design, Class 10 trip, 45 mm wide, 100 kA interrupting capacity at 240 V AC.

Siemens 3RV2421-4AA20 datasheet (PDF)
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

3RV2421-4AA20 — Identification
ParameterValue
SeriesSIRIUS
Product designationCircuit breaker
Frame sizeS0
3RV2421-4AA20 — Electrical
ParameterValue
Rated operational current (Ie)16 A
Rated voltage20 ... 690 V
Rated voltage, AC-3 (max.)690 V
Rated frequency50 ... 60 Hz
Rated insulation voltage (Ui), pollution degree 3690 V
Rated impulse withstand voltage (Uimp)6 kV
Number of poles3
Power loss (AC, hot)9.25 W
Power loss, per pole (AC, hot)3.1 W
3RV2421-4AA20 — Protection & Tripping
ParameterValue
Overload release setting range10 ... 16 A
Instantaneous short-circuit trip current286 A
Trip classCLASS 10
Breaking capacity at 240 V (AC)100 kA
Breaking capacity at 400 V (AC)55 kA
Breaking capacity at 500 V (AC)10 kA
Breaking capacity at 690 V (AC)4 kA
Breaking capacity at 240 V100 kA
Breaking capacity at 690 V2 kA
Short-circuit trip typemagnetic
Overload release typethermal
Short-circuit protectionYes
Phase-failure detectionYes
Ground-fault detectionNo
Auxiliary switch extendableYes
3RV2421-4AA20 — Endurance & Switching
ParameterValue
Endurance, main contacts (typ.)100 000
Endurance, auxiliary contacts (typ.)100 000
Switching frequency, AC-3 (max.)15 1/h
Auxiliary CO (changeover) contacts0
3RV2421-4AA20 — Connections
ParameterValue
Main-circuit terminal typespring-loaded terminals
Main-circuit connector arrangementTop and bottom
Conductor cross-section, solid / stranded2x (1 ... 10 mm²)
Conductor cross-section, finely stranded with ferrule2x (1 ... 6 mm²)
Conductor range, AWG (main contacts)2x (18 ... 8)
3RV2421-4AA20 — Mechanical
ParameterValue
Height119 mm
Width45 mm
Depth97 mm
Mounting methodscrew and snap-on mounting onto 35 mm standard mounting rail according to DIN EN 60715
Mounting positionany
3RV2421-4AA20 — Environmental
ParameterValue
Operating temperature-20 ... +60 °C
Storage temperature-50 ... +80 °C
Transport temperature-50 ... +80 °C
Relative humidity (operation)10 ... 95 %
Max. installation altitude2 000 m
3RV2421-4AA20 — Specifications
ParameterValue
Design Of The ProductFor transformer protection

Product details

What this breaker is for

Trip Class 10 means it clears overloads fast enough to protect most control transformers without nuisance tripping on inrush.

Interrupting capacity and voltage range

The rated operating voltage spans 20 to 690 V, so it covers standard low-voltage distribution in most regions. Backup fuse coordination is specified: gL/gG 63 A at 400 V, 50 A at 500 V, and 40 A at 690 V. That tells the panel builder exactly what upstream fuse to pair with it for selective coordination.

No screw torque to verify — just strip, insert, and seat. That's tighter than many breakers, useful when cramming into a shallow enclosure.

Frequently asked questions

What is the interrupting capacity of the 3RV2421-4AA20 at 240 V?

100 kA at 240 V AC. At 400 V it's 25 kA, at 690 V it's 2 kA.

What trip class is this breaker?

Trip Class 10 — designed for fast overload clearing on transformer primaries.

Does the 3RV2421-4AA20 detect phase failure?

Yes, phase failure detection is built in. It does not include ground fault detection.

Where can I buy the 3RV2421-4AA20?

Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing confirmed at quote time.

MPN
3RV2421-4AA20