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Siemens 5SY8308-7 — 3-Pole MCB (DIN Rail)

Siemens 5SY8308-7 SENTRON MCB, 3P, C-Curve, 40 kA IEC

MPN5SY8308-7
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Siemens SENTRON 5SY8308-7 miniature circuit breaker, 3-pole, C-curve, 40 kA (IEC 60947-2), 3 MW, quick-assembly DIN rail mount.

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

Specifications

5SY8308-7 — Identification
ParameterValue
Brand nameSENTRON
Number of poles3
Pole configuration3P
Suitability for operationMechanical engineering / industry
5SY8308-7 — Protection
ParameterValue
Tripping characteristic (curve)C
Breaking capacity per IEC 60947-240 kA
Overvoltage categoryIII
IP protection classIP20, with connected conductors
Pollution degree3
5SY8308-7 — Electrical
ParameterValue
Rated voltage (AC, multi-phase)440 V
Voltage type (AC/DC)AC
Supply frequency range50/60 Hz
Power loss per pole at rated current (AC, hot)0.9 W
Mechanical service life (operating cycles, typ.)10 000
Neutral conductor switchingNo
Rated voltage (AC, single-phase)440 V
5SY8308-7 — Mechanical
ParameterValue
Modular width units3
Mounting positionany
Width54 mm
Height90 mm
Depth76 mm
Installation depth70 mm
Terminal tightening torque, max.75 °C
Terminal tightening torque, min.-40 °C
Combined terminal, topYes
Combined terminal, bottomYes
Fastening methodQuick assembly system
SealableYes
Accepts supplementary devicesYes
5SY8308-7 — Environmental
ParameterValue
Halogen-freeYes
Silicone-freeYes
Influence of surrounding temperaturemax. 95% to 55°C, max. 55% to 70°C, max. 35% to 75°C
Vibration resistance (IEC 60068-2-6)±1mm at 5 to 25Hz; 50m/s² at 25 to 150Hz

Product details

It also carries a UL 1077 listing (5 kA at 400 V AC), so it qualifies as a supplementary protector in North American panels where the branch circuit already has a listed OCPD upstream.

Depth is 76 mm (70 mm installation depth).

Environment and derating

Rated for ambient temperatures from -40 °C to 75 °C, but the surrounding air's relative humidity matters: max 95% up to 55 °C, tapering to 35% at 75 °C. That's the manufacturer's derating curve for internal arc quenching — if your panel sits in a hot, humid mill environment, factor that in. IP20 with connected conductors — finger-safe terminals when wired, but not protected against dripping water or dust ingress. Sealable cover allows a lockout/tagout hasp to be fitted — required on some safety circuits to prevent an unauthorized restart.

Compliance documentation covers IEC/EN 60947-2, UL 1077, and CSA C22.2 No. 235. Vibration resistance per IEC 60068-2-6 (±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz) is adequate for installation on a machine baseplate or inside a mobile equipment panel.

MPN
5SY8308-7