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Siemens 3RV1321-1FC10 — Motor Protection Circuit Breakers (MPCB)

Siemens 3RV1321-1FC10 SIRIUS Circuit Breaker, 5 A, 100 kA

MPN3RV1321-1FC10

Siemens SIRIUS 3RV1321-1FC10, motor-protective circuit breaker for starter combinations, 3-pole, 5 A rated current, 100 kA breaking capacity at 400 V AC, screw terminals, DIN rail mount.

Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Jul 2026

Specifications

3RV1321-1FC10 — Identification
ParameterValue
SeriesSIRIUS
Product designationcircuit breaker
3RV1321-1FC10 — Electrical
ParameterValue
Rated impulse withstand voltage (Uimp)6 000 V
Number of poles3
Power loss (AC, hot)7.25 W
Power loss, per pole (AC, hot)2.4 W
3RV1321-1FC10 — Protection & Tripping
ParameterValue
Breaking capacity at 240 V (AC)100 kA
Breaking capacity at 400 V (AC)100 kA
Breaking capacity at 500 V (AC)100 kA
Breaking capacity at 690 V (AC)6 kA
Phase-failure detectionNo
Ground-fault detectionNo
Auxiliary switch extendableYes
3RV1321-1FC10 — Endurance & Switching
ParameterValue
Auxiliary CO (changeover) contacts0
3RV1321-1FC10 — Connections
ParameterValue
Main-circuit terminal typescrew-type terminals
Main-circuit connector arrangementfront side
Conductor cross-section, finely stranded with ferrule2x (1 ... 2.5 mm²), 2x (2.5 ... 6 mm²)
Conductor range, AWG (main contacts)2x (14 ... 10)
3RV1321-1FC10 — Mechanical
ParameterValue
Height97 mm
Width45 mm
Depth96 mm
Mounting methodscrew and snap-on mounting onto 35 mm standard mounting rail according to DIN EN 50022
Mounting positionany
3RV1321-1FC10 — Environmental
ParameterValue
Max. installation altitude2 000 m
3RV1321-1FC10 — Specifications
ParameterValue
Design Of The Productfor starter combinations

Product details

It's rated for 5 A continuous current and delivers the same 5 A in AC-3 duty at 400 V, which means it directly protects a 1.5 kW motor at that voltage — no derating guesswork for a standard 4-pole induction motor. Breaking capacity sits at 100 kA up to 500 V AC, dropping to 6 kA at 690 V — that 100 kA figure covers most industrial fault levels on 400 V distribution, so you're not chasing selective coordination nightmares on a typical line.

Any mounting position works; width is 45 mm. Screw-type terminals on both main and auxiliary circuits accept solid, stranded, or finely stranded wire: 2x (1 to 2.5 mm²) and 2x (2.5 to 6 mm²) per clamp. That covers most panel wiring from 14 AWG up to 10 AWG.

What it doesn't do — and why that matters

This breaker has no ground fault detection and no phase failure detection built in. That's by design for a starter-combination breaker — it relies on the upstream feeder protection or a separate electronic relay for those functions. If your application requires ground fault or phase loss tripping, you'll need to add an external module or specify a different variant. It ships with no auxiliary contacts fitted (0 changeover contacts), but the product extension for an auxiliary switch is ready — you can snap one on without pulling the breaker off the rail. Rated for a maximum of 15 operations per hour at AC-3 — that's fine for infrequent start/stop cycles on a pump or fan, but not for a high-duty reversing application or a jogging station.

Surge voltage resistance rated at 6,000 V. Front carries IP20 protection. Shock resistance tested to 25g for 11 ms — survives the ride on a forklift or a slammed cabinet door.

Frequently asked questions

Does 3RV1321-1FC10 include ground fault or phase failure protection?

No. This breaker has no ground fault detection and no phase failure detection built in — those functions must be handled upstream or by an external relay.

What wire sizes fit the terminals on 3RV1321-1FC10?

Screw terminals accept solid, stranded, and finely stranded wire: 2x (1 to 2.5 mm²) and 2x (2.5 to 6 mm²) per clamp, equivalent to 14 to 10 AWG.

MPN
3RV1321-1FC10