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Siemens 3RV2021-4AA25 — Motor Protection Circuit Breakers (MPCB)

Siemens 3RV2021-4AA25 SIRIUS Motor Protection Circuit Breake

MPN3RV2021-4AA25
Active

Siemens SIRIUS motor protection circuit breaker, 3RV2021-4AA25, Trip Class 10, 25 kA breaking capacity at 400 V, 2 hp at 230 V, screw and snap-on mounting onto 35 mm DIN rail.

$48.26Ref. price · indicative, final on quote
Siemens 3RV2021-4AA25 datasheet (PDF)
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

3RV2021-4AA25 — Identification
ParameterValue
SeriesSIRIUS
Product designationCircuit breaker
Frame sizeS0
3RV2021-4AA25 — 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
3RV2021-4AA25 — Protection & Tripping
ParameterValue
Overload release setting range10 ... 16 A
Instantaneous short-circuit trip current208 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
3RV2021-4AA25 — 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
3RV2021-4AA25 — Connections
ParameterValue
Main-circuit terminal typespring-loaded terminals
Main-circuit connector arrangementTop and bottom
Conductor cross-section, solid / stranded2x (0.5 ... 2.5 mm²)
Conductor cross-section, finely stranded with ferrule2x (0.5 ... 1.5 mm²)
Conductor range, AWG (main contacts)2x (18 ... 8)
3RV2021-4AA25 — 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
3RV2021-4AA25 — 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
3RV2021-4AA25 — Specifications
ParameterValue
Design Of The ProductFor motor protection

Product details

Motor protection circuit breaker for 35 mm DIN rail

Rated operating voltage spans 20 to 690 V, covering low-voltage motor circuits from 24 V control transformers up to 690 V industrial mains. Breaking capacity reaches 100 kA at 240 V, 25 kA at 400 V, 5 kA at 500 V, and 2 kA at 690 V — sufficient for most distribution-side fault levels without upstream fuses. Ground fault detection is not included; that requires an add-on module or separate ground-fault relay.

Solid or stranded wire: 2 × (0.5 to 2.5 mm²).

Mounting position is any orientation. Minimum clearances to adjacent metalwork: 50 mm upwards and downwards, 30 mm at the sides, 0 mm forwards and backwards.

Switching capacity and fuse coordination

Maximum back-up fuse ratings for short-circuit coordination: gL/gG 63 A at 400 V, 50 A at 500 V, 40 A at 690 V. Maximum switching frequency in AC-3 duty is 15 operations per hour — sized for motor starting cycles, not continuous load switching. Motor power rating: 2 hp at 230 V. Auxiliary contact ratings: 1 A at 24 V, 0.5 A at 120/125/230 V, 0.15 A at 60 V.

Frequently asked questions

What is the closest functional second-source to 3RV2021-4AA25?

The 3RV2021-4CA25 is a close peer within the same SIRIUS family. Both share the same 45 mm width, Trip Class 10, and DIN rail mounting. The key difference is the 3RV2021-4CA25 has a higher breaking capacity at 400 V (100 kA vs 25 kA for the 4AA25), making it suitable for installations with higher available fault current. The 4AA25 is the standard-duty version; the 4CA25 is the high-breaking-capacity variant. Both use the same terminal technology and clearance requirements, so they are mechanically interchangeable in the same panel footprint.

Will 3RV2021-4AA25 drop into a panel specified around 3RV2021-4CA25 without rewiring?

Yes — both share the same 45 mm width, 97 mm depth, 119 mm height, and screw/snap-on DIN rail mounting. Terminal types and wire ranges are identical. The swap is a straight mechanical replacement; no rewiring or panel modification needed. The only difference is the lower breaking capacity (25 kA vs 100 kA at 400 V), so verify the available fault current at the installation point does not exceed 25 kA.

What compliance documentation does Siemens provide for 3RV2021-4AA25?

As a SIRUS motor protection circuit breaker, this part carries CE marking for the European market and is designed to meet IEC/EN 60947-2 and 60947-4-1 standards. RoHS and REACH compliance declarations are available from Siemens on request. UL/CSA listings are typical for this series but should be confirmed against the specific catalog number for the target jurisdiction.

Where can I buy 3RV2021-4AA25 and how is it quoted?

This part is sourced and quoted to order against an RFQ through independent industrial distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time.

MPN
3RV2021-4AA25