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Siemens 5SY8406-8 — 4-Pole MCB (DIN Rail)

Siemens 5SY8406-8 SENTRON MCB, 4P D 6A, 50kA IEC

MPN5SY8406-8
Active

Siemens SENTRON 5SY8 series, miniature circuit breaker, 4-pole D-curve, 6 A, 400 V AC, 50 kA IEC 60947-2, 72 mm wide, IP20.

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

Specifications

5SY8406-8 — Identification
ParameterValue
Type / order code5SY8
Brand nameSENTRON
Application suitabilityMechanical engineering / industry
5SY8406-8 — Ratings
ParameterValue
Number of poles4
Pole configuration4P
Rated current (In), AC400 V
Rated current (In), AC6 A
Rated voltage, AC (multi-phase)440 V
Rated voltage, AC (single-phase)440 V
Rated voltage, DC (max.)72 V
Voltage typeAC
Rated frequency50/60 Hz
5SY8406-8 — Protection
ParameterValue
Tripping characteristic (trip curve)D
Rated breaking capacity, per IEC 60947-250 kA
Breaking capacity, AC (UL 1077 / CSA C22.2 No.235)5 kA
Overvoltage categoryIII
Degree of protection (IP)IP20, with connected conductors
Neutral conductor switchingNo
Touch protectionYes
5SY8406-8 — Mechanical
ParameterValue
Width in modular units4
Width72 mm
Height90 mm
Depth76 mm
Installation depth70 mm
Mounting positionany
Combined terminal, topYes
Combined terminal, bottomYes
SealableYes
5SY8406-8 — Environmental
ParameterValue
Halogen-freeYes
Silicone-freeYes
Influence of ambient temperature (derating)max. 95% to 55°C, max. 55% to 70°C, max. 35% to 75°C
5SY8406-8 — Performance
ParameterValue
Mechanical service life (switching cycles, typ.)10 000

Product details

Siemens 5SY8406-8 — SENTRON 4-pole D-curve MCB, 6 A, 50 kA

Breaking capacity is 50 kA per IEC 60947-2.

For DC circuits, rated breaking capacity is 15 kA at up to 72 V DC per IEC 60947-2. The D-curve's 10–20× In magnetic trip threshold means this breaker will hold through motor starting currents that would trip a C-curve (5–10× In). For a 6 A rating, the magnetic trip point sits between 60 A and 120 A — enough headroom for a small motor or transformer inrush without sacrificing short-circuit protection.

Environmental and installation notes

Halogen-free and silicon-free construction suits environments sensitive to outgassing, such as clean rooms or food-processing panels. The sealable design allows the panel builder to lock the breaker in the ON or OFF position with a padlock, meeting lockout/tagout requirements without an external accessory.

Frequently asked questions

What wire sizes does the 5SY8406-8 accept?

Solid or stranded conductors from 0.75 mm² up to 35 mm². The combined top and bottom terminals allow through-wiring.

MPN
5SY8406-8