For DC circuits, the maximum rated voltage is 72 V, so this is not a general-purpose DC breaker for higher voltages. The B-curve characteristic (3–5× In) is the most sensitive standard trip curve. It's appropriate for cable protection and loads with low inrush — lighting circuits, control transformers, resistive heaters. It is not intended for motor circuits or capacitive loads where the inrush would cause nuisance tripping. The energy limiting class is 3, meaning it limits let-through energy well, reducing stress on downstream components during a fault. That's adequate for a protection device that operates infrequently; it is not a switching contactor. The ambient temperature derating curve is specified: max 95% RH at 55 °C, dropping to 35% RH at 75 °C — relevant for sealed enclosures or high-temperature railway compartments.
The 18 mm width (1 width unit) occupies one module position. Mounting position is any, so horizontal or vertical rail orientation is acceptable. Touch protection is integrated. Sealable — a lead seal can be fitted to prevent tampering, common in metering or safety-critical rail circuits.