Fixed-mounted circuit breaker, IEC 60947-2, size 1, 3-pole, In=4000 A up to 690 V AC 50/60 Hz, breaking capacity S Icu=66/50 kA at 500/690 V, tripping unit ETU300 LSI optimized for standard applications, without display, basic protection LT, ST, INST, neutral conductor protection requires an external neutral point current sensor, trip alarm switch (1 x CO), connection at rear horizontal.