It uses an ETU330 electronic trip unit with adjustable settings — the overcurrent release is fully programmable for line-protection duty.
The adjustable thermal-magnetic or electronic trip (ETU330) covers a 32 A to 160 A full-scale range, so the same breaker body can serve multiple load sizes by swapping the rating plug or adjusting the dial. The 4-pole design with adjustable N-conductor protection (OFF, 50%, 100%) makes this breaker appropriate for 3-phase + neutral systems where you need to protect the neutral conductor against overload — common in IT or TN-S distribution schemes. Ground-fault monitoring uses summation current sensing on L + N, so it detects leakage without a separate core-balance transformer.