Siemens 3RV2031-4KA10 Motor Protection Circuit Breaker

Product Type: SIRIUS 3RV2 series frame S2 motor protection circuit breaker (motor protector), active production model, made in Germany

1. Model Code Explanation

3RV 2 0 31 4 K A 10

3RV: SIRIUS motor protection circuit breaker

2: 2nd generation of 3RV2 series

0: Standard version, no pre-fitted auxiliary contacts

31: Frame size S2

4: Trip current rating code

K: Thermal setting range 62~73A

A: Screw terminals

10: Standard breaking capacity (without additional contacts)

2. Core Technical Data

3. Protection Functions
4. Overload protection: Inverse-time thermal trip via bimetallic strip, motor overload protection and phase loss protection
5. Short-circuit protection: Instantaneous electromagnetic trip for rapid short-circuit disconnection
6. Front-mounted TEST pushbutton for manual tripping test of the mechanism
7. Handle position indication: ON / OFF / fault trip position; padlockable for lockout
8. Wiring & Installation Specifications

Main circuit conductor: Max. 1×35mm² solid/stranded cable; max. 1×25mm² fine-stranded cable with ferrule

Tightening torque for main terminals: 3.0~4.5 N·m, M6 screws

Accepts top-in or bottom-in wiring; DIN35mm rail mounting

Can be assembled with SIRIUS 3RT contactor to form a direct-on-line starter, constituting a motor protection starter unit

5. Selection & Replacement Information

Same-series Replacement (Same Rating)

3RV2031-4KA15: Version with pre-fitted auxiliary contacts (1NO+1NC)

Note: 3RV2031-4KA10 has no built-in auxiliary contacts. For feedback signals, 3RV2901 auxiliary contact accessory must be mounted externally.

Domestic Alternative Reference

Siemens local China 3RV5/3RV6 series equivalent: 3RV5031-4KA10 (domestic frame S2, 62~73A, screw terminals, largely identical parameters)

6. Typical Applications

3-phase asynchronous motors, fans, water pumps, compressors, conveyor motor circuit protection

Motor starter circuits inside control cabinets, combined with contactors as starter assemblies

Motor protection for machine tools, HVAC, packaging, chemical automation equipment

7. Troubleshooting Guide
8. Trips immediately upon motor start: Usually short-circuit trip. Check motor windings and cables for phase-to-phase or earth short circuit.
9. Trips after running for some time: Overload. Recheck motor rated current and reset the adjustment knob; inspect for mechanical jamming.
10. Cannot close: Mechanism fault, or previous short-circuit trip not fully reset. Press TEST button to reset before closing.
11. Second-hand Inspection Checklist
12. Appearance: No cracked housing, burn marks, or overheating discoloration on terminals
13. Mechanical operation: Smooth handle operation; TEST button triggers trip correctly and resets properly
14. Continuity: Main contacts conduct when closed and isolate when open; no internal short circuit
15. Insulation: Measure insulation resistance between phases and to earth using a megger

Siemens 3RV2031-4KA10 (Frame S2) Installation Dimensions

All 3RV2031 models of frame S2 share identical outer dimensions

Unit Overall Dimensions (W × H × D)

Width W: 55 mm (55mm cabinet space per unit)

Height H: 140 mm

Depth D: 149 mm (from rail mounting surface to front of operating handle)

Mounting Method

Rail: DIN 35mm standard rail (DIN EN 60715), clip-on mounting; optional screw locking

Mounting orientation: any orientation (vertical, horizontal installation allowed)

Cabinet Clearances (Heat dissipation / Electrical clearance)

Side-by-side mounting: 0mm gap allowed for adjacent units

Vertical clearance top & bottom: ≥50mm at upper/lower terminal zones

Clearance to earthed cabinet metalwork: ≥10mm lateral clearance

Cabinet cutout (if door extension handle is used)

The 3RV2 unit is DIN-rail mounted inside the cabinet. If an extended door operating handle (sold separately) is required:

Cutout width: approx. 48mm, cutout height: approx. 130mm

Note: No cabinet cutout required without extension handle; unit is fully installed inside enclosure on DIN rail.

Supplementary Notes

With 3RV2901 side-mounted auxiliary contact: overall width unchanged, slight increase in depth

When back-to-back assembled with 3RT contactor as starter: total depth equals sum of both components

Siemens 3RV2031-4KA10 Weight

✅ Net weight (unit only, no packaging): 1.17 kg (manufacturer nominal 1.172 kg; use 1.17kg on engineering drawings)

All S2 frame 3RV2031 models have similar weight, range 1.07~1.18 kg. Variations come from internal trip components; standard value for 3RV2031-4KA10 is 1.17 kg.

Supplementary Notes

1. Excluding accessories: No 3RV2901 auxiliary contacts, door extension handles or other attachments. Weight increases slightly when accessories are fitted.
2. Gross weight with factory carton: approx. 1.30 kg (for logistics estimation)
3. Unit conversion: 1.17 kg ≈ 2.58 lbs

Siemens 3RV2031-4KA10｜Cross-brand Comparison + MPCB Product Series List

Reference device: 3RV2031-4KA10, frame S2, 55mm width, 3P, 62~73A, screw terminals, Class10, Icu@400V=65kA, no built-in auxiliary contacts, for 37kW@400V motor

⚠️ Important notice: No fully pin-to-pin drop-in replacement available. The below are function/rating/frame equivalent selections. Cabinet mounting, accessories, breaking capacity and instantaneous trip values must be verified. Protection coordination validation is mandatory before formal project replacement.

1. Siemens Internal Cross-reference (Preferred Replacement)

3RV2 frame size overview

S00: 45mm, max 16A, motor ≤7.5kW

S0: 45mm, max 40A, motor ≤18.5kW

S2: 55mm, max 80A, motor ≤37kW (frame of this model)

S3: 70mm, max 100A, motor ≤45~55kW

2. Imported Brand Equivalent Cross-reference (62~73A, S2 frame class MPCB)

3. Domestic Brand Alternatives (Cost Reduction for Projects)

4. MPCB Product Portfolio Overview by Brand (Thermal-Magnetic DIN Rail Motor Protection Circuit Breaker)

Siemens

3RV2 (SIRIUS main import range: S00/S0/S2/S3, 0.1~100A)

3RV5 / 3RV6 (domestic economical range, S00/S0/S2)

3RV1 (legacy model, phasing out)

3VU (old compact type, max 63A)

Schneider

GV2: Small frame 45mm, 0.1~40A

GV3: Medium frame 55mm, 40~80A (counterpart to 3RV2 S2)

GV7: Large frame, 80~150A

ABB

MS116: Small frame

MS132: Medium frame, max 32A

MS165: 55mm frame up to 80A (counterpart to 3RV2 S2)

MO series (high breaking capacity version)

Eaton (Moeller)

PKZ0 / PKZ1: Low current

PKZ2: S2 frame up to 80A

PKZ3: Large frame

Main Domestic Brands

Chint NS2

Delixi CDV6

Nader NDM2-M

Changshu CM1-M (motor protection variant)

5. Risks for Replacement Selection (Critical for Engineering)
6. Different instantaneous short-circuit trip (N factor): 3RV2031-4KA10 fixed at 949A. Schneider GV3 and ABB MS165 have different electromagnetic trip thresholds. Short-circuit protection coordination changes. Direct replacement may cause loss of selectivity.
7. Ultimate breaking capacity Icu: 3RV2 is 65kA@400V. Domestic models generally have lower Icu and shall NOT be used for circuits with high prospective short-circuit current.
8. Mechanical interlock & contactor assembly: 3RV2 can directly snap onto 3RT contactor to form starter. Cross-brand devices cannot mechanically clip together, separate mounting brackets required.
9. Auxiliary contact accessory systems are incompatible; mounting depth, terminal torque and maximum cable cross-section differ.
10. UL/CE certification: No arbitrary brand replacement for export machines.
11. Recommended Selection Rules

Cabinet retrofit, minimal modification: Siemens 3RV5031-4KA10 (domestic same-brand replacement)

Import brand substitution: Schneider GV3ME80 / ABB MS165-73, short-circuit protection coordination recheck required

Non-critical domestic circuit cost saving: Chint NS2-80 / Delixi CDV6-80