The ETU560 is a microprocessor-based trip unit with LSIG functions. Overload protection (Ir) is adjustable from 100 A to 250 A, so you dial in the continuous current to match the cable or busbar rating — not just the breaker frame. Short-time pickup (Isd) spans 0.6 to 10 times In, and instantaneous pickup (Ii) runs 1.5 to 10 times In. Ground-fault protection (Ig) is adjustable from 0.2 to 1 times In with a time delay tg of 0.05 to 0.8 seconds, and it can be switched off entirely if the installation uses a separate GFCI. The neutral conductor protection is also adjustable (OFF, up to 100% of In). That level of adjustability means one breaker covers a wide range of feeder and main applications — you set the taps at commissioning, not at ordering.
Integrated accessories — undervoltage release and auxiliary switches
The auxiliary switches report the breaker position (open/closed) and the trip alarm signals a fault trip, not a manual open.
The 3VA2 frame 250 mounts with four screws onto a mounting plate or into a switchboard — it is not a DIN-rail snap-on breaker. The nut keeper kit mentioned in the description holds the mounting nuts captive, which saves time when you are assembling the breaker into a panel with limited rear access. Plan for the 4-pole footprint: it occupies roughly 280 mm width on the mounting plate, and the line and load lugs accept copper or aluminum conductors sized for 250 A continuous. The undervoltage release coil draws continuously when energized; factor that into the control transformer sizing if you are feeding multiple releases from one source.