The Siemens 3VA9403-0JC23 is a SENTRON TA2.4 circular conductor terminal — a wire connector designed to terminate two copper or aluminum cables into a single compression point on 3VA1 and 3VA2 molded-case circuit breakers in the 400 A and 630 A frame sizes. It is an accessory, not a standalone device; it mounts on the breaker's line or load side to consolidate parallel feeds. A built-in control wire voltage tap-off lets you pick off a lower-gauge sense or control voltage directly at the breaker terminal, eliminating a separate tap block on the bus. Stripped length is 1.2 in for the main conductor and 2.3 in for the tap, so the wire prep is straightforward — strip, insert, torque.
The 3VA9403-0JC23 carries an active lifecycle status. It is a current-production SENTRON accessory, not a phase-out or NRND line.
The 600 kcmil maximum on both copper and aluminum means this connector handles the full ampacity of a 400 A or 630 A breaker without needing a reducer or a second lug. The 2/0 AWG minimum covers the smaller parallel feeds often used in tap-off or subfeed configurations. If your wire size falls outside that range — say, 750 kcmil or 1/0 AWG — this terminal won't grip properly.