What the ratings mean for fit
The 5SU1624-2RC32 is a combined residual-current circuit breaker with overcurrent protection (RCBO) rated 32 A, 2-pole, in a 4-module DIN-rail housing. The D characteristic means its magnetic trip curve is designed for loads with high inrush currents — motor starters, small drives, or transformer primaries — where a B or C curve would nuisance-trip on startup. The Type AC residual-current element (300 mA) detects sinusoidal AC earth faults only; it is the standard choice for general-purpose socket circuits and lighting where no pulsed DC fault current is expected. The 4-module width (roughly 72 mm on a standard DIN rail) determines how many units fit a given enclosure row.