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Siemens 5SY8405-7 — 4-Pole MCB (DIN Rail)

Siemens SENTRON 5SY8405-7 4-Pole MCB, C-Curve 0.5 A, 70 kA

MPN5SY8405-7
Active

Siemens SENTRON series, miniature circuit breaker, 4-pole, 0.5 A rated current, C tripping characteristic, 70 kA breaking capacity per IEC 60947-2, 50/60 Hz, IP20 with connected conductors.

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

Specifications

5SY8405-7 — Identification
ParameterValue
Brand nameSENTRON
Application suitabilityMechanical engineering / industry
5SY8405-7 — Ratings
ParameterValue
Number of poles4
Pole configuration4P
Rated current (In), AC0.5 A
Rated voltage, AC (multi-phase)440 V
Rated voltage, AC (single-phase)440 V
Voltage typeAC
5SY8405-7 — Protection
ParameterValue
Tripping characteristic (trip curve)C
Rated breaking capacity, per IEC 60947-270 kA
Breaking capacity, AC (UL 1077 / CSA C22.2 No.235)5 kA
Overvoltage categoryIII
Pollution degree3
Degree of protection (IP)IP20, with connected conductors
Neutral conductor switchingNo
Touch protectionYes
5SY8405-7 — Mechanical
ParameterValue
Width in modular units4
Width72 mm
Height90 mm
Depth76 mm
Installation depth70 mm
Fastening / mounting methodQuick assembly system
Mounting positionany
Combined terminal, topYes
Combined terminal, bottomYes
Tightening torque, max.75 °C
Tightening torque, min.-40 °C
SealableYes
5SY8405-7 — 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

Product details

Rated 0.5 A at 45 °C and derated to 0.49 A at 50 °C and 0.47 A at 55 °C, so if the enclosure runs warm, the actual continuous current it can carry drops; factor that into the load calculation if the panel is in a hot cabinet.

Breaking capacity and selectivity in a real panel

The 70 kA rating per IEC 60947-2 is the headline number, but the part also carries a 15 kA DC breaking capacity per the same standard and a 5 kA rating per UL 1077 and CSA C22.2 No. 235 — so it's certified for both IEC and North American panels, though the UL/CSA rating is lower and governs any listing in those jurisdictions. Vibration resistance tested to IEC 60068-2-6 at ±1 mm from 5 to 25 Hz and 50 m/s² from 25 to 150 Hz, so it holds up on a machine frame or in a mobile equipment panel, not just a stationary wall-mount board.

Integration into a panel — dimensions and wiring

Width is 72 mm (4 modular units), height 90 mm, depth 76 mm, installation depth 70 mm. Combined terminals on both top and bottom accept the same conductor range, and the part is sealable — useful for applications where the panel must be locked after commissioning to prevent tampering. Halogen-free and silicon-free construction matters in environments where outgassing from a fault could contaminate optics or electronics — think semiconductor fabs, medical device manufacturing, or cleanroom-adjacent panels.

Frequently asked questions

What is the temperature range for 5SY8405-7?

The operating ambient temperature range is -40 °C to 75 °C, with humidity limits of 95% up to 55 °C, 55% up to 70 °C, and 35% up to 75 °C.

MPN
5SY8405-7