Skip to main content
Siemens 3RV1421-1KA15 — Motor Protection Circuit Breakers (MPCB)

Siemens 3RV1421-1KA15 SIRIUS Circuit Breaker, 12.5 A, CLASS

MPN3RV1421-1KA15

Siemens SIRIUS circuit breaker for transformer protection, 3RV1421-1KA15, 12.5 A continuous, CLASS 10 trip, 100 kA SCCR at 400 V AC, screw-type terminals, IP20 front.

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

3RV1421-1KA15 — Identification
ParameterValue
SeriesSIRIUS
Product designationcircuit breaker
3RV1421-1KA15 — Electrical
ParameterValue
Rated voltage690 V
Rated voltage, AC-3 (max.)690 V
Rated impulse withstand voltage (Uimp)6 000 V
Number of poles3
Power loss (AC, hot)9.25 W
Power loss, per pole (AC, hot)3.1 W
3RV1421-1KA15 — Protection & Tripping
ParameterValue
Trip classCLASS 10
Breaking capacity at 240 V (AC)100 kA
Breaking capacity at 400 V (AC)100 kA
Breaking capacity at 500 V (AC)42 kA
Breaking capacity at 690 V (AC)6 kA
Phase-failure detectionYes
Ground-fault detectionNo
3RV1421-1KA15 — Endurance & Switching
ParameterValue
Endurance, main contacts (typ.)100 000
Switching frequency, AC-3 (max.)15 1/h
3RV1421-1KA15 — Connections
ParameterValue
Main-circuit terminal typescrew-type terminals
Main-circuit connector arrangementfront side
Conductor cross-section, finely stranded with ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
3RV1421-1KA15 — Mechanical
ParameterValue
Height97 mm
Width45 mm
Depth96 mm
Mounting positionany
3RV1421-1KA15 — Environmental
ParameterValue
Operating temperature-20 ... +60 °C
Storage temperature-50 ... +80 °C
Transport temperature-50 ... +80 °C
3RV1421-1KA15 — Specifications
ParameterValue
Design Of The Productfor transformer protection

Product details

Transformer-protection breaker, 12.5 A, CLASS 10 — what you're getting

At 45 mm wide and 97 mm tall, it fits a standard MCCB or motor-protective breaker footprint in the panel. Depth is 96 mm, so factor that into your gland-plate clearance if the breaker sits near the enclosure back wall.

SCCR and interrupting capacity — the real numbers for your panel label

This breaker carries a 100 kA short-circuit current rating at 240 V and 400 V AC, dropping to 42 kA at 500 V and 6 kA at 690 V. Rated operational voltage tops out at 690 V AC, with a maximum operating altitude of 2 000 m. Shock-rated to 25g for 11 ms — it'll hold up on a machine that sees occasional jolts.

Terminals and wiring

Solid wire accepts 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²); stranded takes 2x (1 to 2.5 mm²) or 2x (2.5 to 6 mm²). That covers standard control-panel wiring from 18 AWG up to about 10 AWG. The auxiliary switch is a transverse design — included, with zero dedicated auxiliary contacts on the main block, so the internal switch handles signaling.

Frequently asked questions

How do I get current pricing and availability for 3RV1421-1KA15?

Submit an RFQ through this listing. Availability and current pricing are confirmed at quote time through our independent distribution channels — we don't publish live stock numbers here.

Will 3RV1421-1KA15 drop into a panel that was specified around 3RV2021-1FA15 without rewiring?

The 3RV2021-1FA15 is a different frame size — it's a 45 mm wide motor-protective breaker from the same SIRIUS family, but the 3RV1421 is a transformer-protection variant with a different trip curve. Both mount on 35 mm DIN rail, but verify the terminal arrangement and auxiliary contact layout against your existing wiring plan before swapping; the screw terminals accept the same wire ranges, so re-termination is straightforward if the footprint matches.

What compliance documentation does this brand provide for 3RV1421-1KA15 (RoHS, REACH, UL, IEC)?

Siemens SIRIUS components typically carry CE marking per IEC/EN 60947 series and are UL/CSA recognized for the North American market. RoHS and REACH declarations are available from Siemens' documentation portal. Specific cert numbers for this order code should be verified against the nameplate or Siemens Industry Online Support.

MPN
3RV1421-1KA15