D-curve MCB for high-inrush loads
The Siemens SENTRON 5SY8463-8BB08 is a 4-pole miniature circuit breaker with a D tripping characteristic, rated 20 kA interrupting capacity at 400 V AC. The D curve tolerates high inrush currents typical of motor starters and transformers. Occupies 4 modular width units (72 mm) on a DIN rail, with a depth of 76 mm and a height of 90 mm. Mounts in any position and accepts supplementary devices (auxiliary contacts, shunt trips, alarm switches) via the product extension interface.
Lifecycle and sourcing
Listed as current-production (active lifecycle stage). No end-of-life notification. Sourced and quoted to order against an RFQ through independent distribution.
Environmental and installation ratings
Rated for ambient temperatures from -40 °C to +75 °C, with humidity derating above 55 °C (95% RH to 55 °C, 55% RH to 70 °C, 35% RH to 75 °C). IP20 with connected conductors, pollution degree 3, overvoltage category III. Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz. Halogen-free and silicon-free construction. Sealable design allows locking in the ON or OFF position for lockout/tagout compliance. Neutral conductor is not switched — the 4-pole unit switches three phases plus a switched neutral? Verify: the evidence states neutral conductor switching is 'No', so this is a 3-phase + solid neutral pass-through configuration, not a fully switched 4-pole. The combined terminal top and bottom accept both busbar and screw-clamp wiring.
UL and DC ratings
Under UL 1077 and CSA C22.2 No. 235, the interrupting capacity is 5 kA. Maximum DC operating voltage is 72 V. These ratings matter for panels destined for North American installations or DC control circuits — the 20 kA IEC rating does not carry over to UL listings, so a panel builder must coordinate the SCCR using the 5 kA figure for UL 508A compliance.