Siemens SENTRON 5SY7313-8CC — 3-pole D-curve MCB, 13 A, 25 kA
The Siemens SENTRON 5SY7313-8CC is a 3-pole miniature circuit breaker with a D tripping characteristic, rated at 13 A at 400 V AC. It is part of the 5SY7CC design series, built for mechanical engineering and industrial panel applications where high inrush currents — motor starts, transformer energization, or welding loads — demand a D-curve to avoid nuisance trips. The 25 kA breaking capacity per IEC 60947-2 means it can safely interrupt a fault up to that level without cascading upstream; the 5 kA rating per UL 1077 and CSA C22.2 No. 235 covers North American branch-circuit installations. Mounting is via the quick assembly system — snaps onto DIN rail, any position, with an installation depth of 70 mm and overall depth of 76 mm. The 54 mm width (3 width units) and 90 mm height fit standard SENTRON enclosure layouts. Terminals accept solid or stranded conductors from 0.75 to 35 mm²; tightening torque is 2.5 to 3.5 N·m. The combined terminal design at both top and bottom simplifies busbar and cable routing. Rated for ambient temperatures from -25 to +55 °C, storage from -40 to +75 °C. The housing is halogen-free and silicon-free, and the breaker is sealable for tamper-proof installations. Touch protection is built in, and the IP20 rating applies with connected conductors — standard for enclosed panel use.
D-curve selectivity and coordination
The D-curve (tripping characteristic class D) is the key differentiator from the more common B- or C-curve MCBs in the SENTRON family. Where a C-curve trips at 5–10× rated current, the D-curve allows 10–20× In — typically 130 to 260 A instantaneous trip for this 13 A unit. That headroom is essential when the breaker feeds a motor starter, a transformer primary, or a bank of power supplies that draw a short-duration inrush well above the running load. The trade-off is less protection for long, low-overload events; coordination with downstream overload relays or fuses is the normal practice. Compared to a C-curve sibling like the 5SY7210-7CC (10 A, C-curve), the 5SY7313-8CC carries a higher continuous rating and a wider instantaneous band. The 5SY3132-6 (a 3-pole C-curve 32 A unit) would not be a drop-in substitute — different curve, different rating, and the 5SY7CC design series uses a different terminal architecture. If your BOM specifies a 13 A D-curve, the 5SY7313-8CC is the correct SENTRON order code; no parametric cross within the same footprint exists.
Panel integration
Snaps onto DIN rail via the quick assembly system. The 54 mm width (3 width units) and 70 mm installation depth fit standard SENTRON distribution boards and sub-distribution panels. Any mounting position is permitted. The combined terminal at top and bottom accepts solid or stranded copper up to 35 mm²; torque to 2.5–3.5 N·m. Sealable cover available for tamper-proof installations. Halogen-free and silicon-free housing suits clean-room or food-industry enclosures where outgassing is a concern.