Siemens Betagard 5SL4106-0RC — 6 A, Z-characteristic MCB
The Z curve trips between 2 and 3 times rated current — tighter than a B curve — so it catches semiconductor or control-transformer overloads before they cook the winding, but won't nuisance-trip on normal inrush from a 24 VDC supply. Rated voltage hits 440 V AC in single- or multi-phase operation, and DC rating maxes at 72 V — enough for most control-circuit rails.
Z-curve application and thermal derating
The Z characteristic (2–3× In trip band) is the main reason you'd pick this over a B or C curve: it protects circuits where even a brief 4× overload would damage downstream electronics — PLC power supplies, fieldbus couplers, instrumentation loops. At 30 °C ambient the breaker carries 6.5 A; at 50 °C it's back to 6 A; at 60 °C it's 5.7 A. Mounting position is unrestricted, so you can lay it sideways in a shallow gland box if needed.
Snap-on DIN-rail mount, 18 mm wide (1 MW). Sealable (padlockable toggle) for lockout/tagout. Halogen-free and silicon-free construction, which matters for clean-room or high-reliability environments where outgassing contaminates contacts or optics.