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Siemens 3RV2121-4DA10 — Motor Protection Circuit Breakers (MPCB)

Siemens 3RV2121-4DA10 SIRIUS Motor Protection Circuit Breake

MPN3RV2121-4DA10
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Siemens SIRIUS 3RV2121-4DA10 motor protection circuit breaker with integrated overload relay, Class 10 trip, screw & snap-on DIN rail mount, 97 mm depth.

$72.39Ref. price · indicative, final on quote
Siemens 3RV2121-4DA10 datasheet (PDF)
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

3RV2121-4DA10 — Identification
ParameterValue
SeriesSIRIUS
Product designationCircuit breaker
Frame sizeS0
3RV2121-4DA10 — 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
3RV2121-4DA10 — Protection & Tripping
ParameterValue
Overload release setting range18 ... 25 A
Instantaneous short-circuit trip current325 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
3RV2121-4DA10 — 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
3RV2121-4DA10 — Connections
ParameterValue
Main-circuit terminal typescrew-type terminals
Main-circuit connector arrangementTop and bottom
Conductor cross-section, solid / stranded2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Conductor cross-section, finely stranded with ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Conductor range, AWG (main contacts)2x (16 ... 12), 2x (14 ... 8)
3RV2121-4DA10 — Mechanical
ParameterValue
Height97 mm
Width65 mm
Depth97 mm
Mounting methodscrew and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715
Mounting positionany
3RV2121-4DA10 — 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
3RV2121-4DA10 — Specifications
ParameterValue
Design Of The ProductFor motor protection with overload relay function

Product details

Breaking capacity hits 100 kA at 240 V, 25 kA at 400 V, 5 kA at 500 V, and 2 kA at 690 V — so it stays selective downstream of a larger feeder breaker in most 400 V industrial panels. Phase-failure detection is built in; ground-fault detection is not.

Maximum operating frequency is 15 switching cycles per hour in AC-3 (motor) duty. Dimensions are 65 mm wide, 97 mm tall, 97 mm deep — a standard three-module-wide footprint for the SIRIUS 3RV2 frame. Screw terminals on the main circuit accept 2×(0.5…1.5 mm²) or 2×(0.75…2.5 mm²) solid or stranded. The rated insulation voltage spans 20…690 V. For the main contact screws, use M4.

Frequently asked questions

Where can I buy 3RV2121-4DA10 and how do I get a price?

This part is sourced and quoted to order against an RFQ. Submit a request through the site; availability and current pricing are confirmed at quote time.

Will 3RV2121-4DA10 drop into a panel that was specified around 3RV2121-4CA10 without rewiring?

The 3RV2121-4DA10 and 3RV2121-4CA10 share the same SIRIUS 3RV2 frame — same 65 mm width, same 97 mm depth, same DIN-rail mounting and screw-terminal pattern. Physical interchange is direct; verify the thermal setting range and breaking capacity match your motor's data.

MPN
3RV2121-4DA10