What this 4-pole D-curve MCB does for your panel
The Siemens 5SY6432-8CC is a 4-pole miniature circuit breaker from the SENTRON 5SY6 series, rated 32 A at 400 V AC with a D tripping characteristic. The 5SY6CC design includes touch protection and is sealable for tamper-evident metering or rental applications.
The D-curve is the key selector here. Unlike a B-curve (lighting, resistive) or C-curve (general-purpose), D-curve allows 10–20× rated current for a short duration before tripping magnetically. That's what you need when the load is a motor, a power supply bank, or a transformer — the inrush won't pop the breaker on energization. The 32 A rating at 400 V AC three-phase gives you about 22 kW of connected motor load (assuming 0.85 PF), which is a solid mid-range feeder or a large individual motor circuit. Breaking capacity is 6 kA per EN 60898 and 5 kA per UL 1077 / CSA C22.2 No. 235. If your installation is in a North American panel with a higher available fault current, the 5 kA UL figure is the binding limit — verify your SCCR before committing. The 72 V DC maximum rating means this MCB can switch DC control circuits up to that voltage, but it's primarily an AC device.
Panel integration checklist
Depth is 76 mm, height 90 mm, width 72 mm (4 MW). Installation depth into the enclosure is 70 mm — the extra 6 mm is the terminal overhang. Combined terminals top and bottom mean you can feed from either direction.