The Siemens 5SL6240-7MB is a SENTRON miniature circuit breaker rated 40 A with a C tripping characteristic, 2-pole design, and a 6 kA breaking capacity per EN 60898 at 400 V AC. The C-curve means it handles moderate inrush — typical for motor, lighting, and general distribution circuits — tripping between 5 and 10 times rated current. That 6 kA rating is the fault current it can safely interrupt under the standard; at 400 V three-phase it's suitable for residential and light commercial infrastructure. It occupies 2 modular width units (36 mm) on a DIN rail, so it fits standard panel layout without surprises.
Mounts on DIN rail in any position. Depth of 76 mm (70 mm installation depth) leaves clearance for wiring and busbar connections. Sealable design allows tamper-proof sealing for metering or safety circuits. IP20 with connected conductors — standard for enclosed panel use.
Rated for 50/60 Hz, 400 V AC multi-phase (440 V max) or 250 V single-phase. DC rated to 72 V max. Power loss 3.3 W per pole at rated current in hot state — factor into thermal budgeting for enclosed panels. Pollution degree 2, overvoltage category III, energy limitation class 3. Accepts supplementary devices (auxiliary contacts, shunt trips, undervoltage releases).