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Siemens 3RV2321-4DC20 — Motor Protection Circuit Breakers (MPCB)

Siemens 3RV2321-4DC20 SIRIUS Circuit Breaker, 55 kA at 400 V

MPN3RV2321-4DC20
Active

Siemens SIRIUS circuit breaker, 3RV2321-4DC20, for starter combinations, 45 mm wide, 55 kA breaking capacity at 400 V AC, screw and snap-on mounting onto 35 mm DIN rail.

$46.99Ref. price · indicative, final on quote
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

3RV2321-4DC20 — Identification
ParameterValue
SeriesSIRIUS
Product designationCircuit breaker
Frame sizeS0
3RV2321-4DC20 — Electrical
ParameterValue
Rated operational current (Ie)25 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)10.5 W
Power loss, per pole (AC, hot)3.5 W
3RV2321-4DC20 — Protection & Tripping
ParameterValue
Instantaneous short-circuit trip current325 A
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
Short-circuit protectionYes
Phase-failure detectionNo
Ground-fault detectionNo
Auxiliary switch extendableYes
3RV2321-4DC20 — 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
3RV2321-4DC20 — 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)
3RV2321-4DC20 — Mechanical
ParameterValue
Height119 mm
Width45 mm
Depth97 mm
Mounting methodscrew and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715
Mounting positionany
3RV2321-4DC20 — 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
3RV2321-4DC20 — Specifications
ParameterValue
Design Of The ProductFor starter combinations

Product details

Mounting and environment

That covers unheated warehouses and hot control rooms alike. Clearance requirements: 50 mm upwards and downwards, 30 mm to the side, zero forwards or backwards — so the breaker can sit flush against a backplate.

Breaking capacity and ratings

Breaking capacity varies by voltage: 100 kA at 240 V AC, 55 kA at 400 V AC, 25 kA at 480 V, 5 kA at 500 V, and 2 kA at 690 V.

Terminals and wiring

Main current circuit uses spring-loaded terminals — no screw tightening, just strip and push. Accepts solid or stranded copper: 2 x 1 to 10 mm² per terminal. That covers most motor branch wiring up to about 25 A full load. No ground fault or phase failure detection built in — this is a straightforward thermal-magnetic breaker, not an electronic motor protector.

Frequently asked questions

Where can I buy 3RV2321-4DC20?

This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time.

What is the closest functional second-source to 3RV2321-4DC20?

The 3RV2023-4DA10 is a peer in the same SIRIUS family, but it's a different frame size — the 3RV2321-4DC20 has a 45 mm width and 55 kA breaking capacity at 400 V, while the 3RV2023-4DA10 is narrower and has lower interrupting ratings. Verify panel cutout and fault current requirements before substituting.

Will 3RV2321-4DC20 drop into a panel specified around 3RV2023-4DA10 without rewiring?

Not directly — the 3RV2321-4DC20 is 45 mm wide, while the 3RV2023-4DA10 is a different width. Check the existing DIN rail spacing and terminal arrangement; the spring-loaded terminals accept the same wire sizes, but physical fit must be confirmed.

MPN
3RV2321-4DC20