40 A D-curve MCB for 3+N-pole distribution
The Siemens 5SL4640-8CC is a 3+N-pole miniature circuit breaker rated 40 A with a D tripping characteristic, breaking capacity of 10 kA at 400 V. The D-curve (10–20× In) is sized for high inrush loads — motor starters, drives, or transformer primaries where an instantaneous trip would nuisance-trip on energization. RoHS compliant since June 2013 and REACH candidate-list declared. The product class B flags a return-restricted material — if a warranty claim arises, coordinate with the Siemens partner before shipping back.
Selectivity and coordination in a panel
The 10 kA breaking capacity at 400 V sets the maximum fault current this MCB can safely interrupt without upstream damage. In a typical distribution board, verify the prospective short-circuit current (PSCC) at the point of installation stays under 10 kA — otherwise a higher-rated upstream device (e.g., an SENTRON 3VA molded-case breaker) must provide backup protection. D-curve at 40 A means the magnetic trip fires between 400 A and 800 A. That window avoids nuisance trips on motor start but still clears a hard bolted fault fast enough for cable protection. For a 40 A feeder feeding a 22 kW motor (FLA ~42 A at 400 V), the D-curve is the right call; a B or C curve would trip on the inrush.
Compliance package for documentation
RoHS declaration dated June 2013 and REACH candidate-list disclosure are on file. Export control is AL:N / ECCN:N — no dual-use license required for cross-border shipment. The product group (3824) and group code (P310) are Siemens internal cataloging fields for BOM traceability and spare-part cross-reference.