Transformer-protection circuit breaker, size S00
It mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 60715, in any position — the 97 × 45 × 97 mm envelope (depth, width, height) fits standard panel layouts without special gland-plate allowances. Rated operating voltage spans 20 to 690 V. Breaking capacity reaches 100 kA at 400 V AC and 500 V AC, dropping to 10 kA at 690 V AC — adequate for transformer primary-side fault clearing in most industrial distribution panels. Coordination with upstream gG fuse-links: rated 25 A at 400 V and 500 V, 20 A at 690 V. Maximum switching rate under AC-3 duty is 15 operations per hour — sufficient for infrequent transformer energization, not for cyclic motor starting.
Screw-type terminals on the main current circuit accept 2 × (0.75 to 2.5 mm²) solid or stranded, or 2 × 4 mm². Terminal screws take a Pozidriv size 2 tip or a 5–6 mm diameter screwdriver shaft. Clearance: 50 mm upwards and downwards, 30 mm at the sides; zero forwards or backwards.
