What this MCCB carries — and what the ratings mean for your panel
The Siemens 3VA2116-5HN42-0BA0 is a 4-pole IEC frame 160 molded case circuit breaker rated for line protection, built around the ETU350 electronic trip unit with LSI (long-time, short-time, instantaneous) protection curves. The headline number is the 55 kA breaking capacity at 415 V AC — breaking capacity class M — which means it can safely interrupt a fault current up to 55,000 amps without welding contacts or venting gas into the enclosure. That puts it squarely in the range for industrial main feeders and large sub-distribution boards where the available fault current is high and selectivity with downstream breakers matters. The continuous current rating is 160 A, with the overload protection (Ir) adjustable from 63 A to 160 A via the ETU350 dials. Short-time pickup (Isd) is settable from 1.5× to 10× Ir, and the instantaneous pickup (Ii) is fixed at 10× In. The neutral conductor protection is also adjustable — OFF, 50%, or 100% of the phase current — which is useful for 4-wire systems where neutral loading varies. All of this is set on the trip unit face without needing external power or programming tools. This particular unit ships with a factory-installed 24 V DC undervoltage release accessory, intended for the 3VA1 and 3VA20 platform. An undervoltage release trips the breaker when the control voltage drops below a threshold — common in emergency-stop chains or upstream contactor interlocking where a loss of control power must open the main breaker. The release is wired separately from the load circuit; verify polarity on the 24 V DC coil before energizing.
Integration and mounting — DIN-rail or screw-mount panel fit
The 3VA2 frame 160 mounts on a standard DIN rail or via four screw holes onto a backplate. At 160 A frame size, expect the breaker to occupy roughly four to six module widths — plan the enclosure fill factor accordingly, especially if you are retrofitting into an existing panel where busbar take-off points are fixed. The nut keeper kit mentioned in the description is a captive-nut accessory that simplifies screw-mounting in enclosures where the back-of-panel access is tight. The ETU350 is a self-powered electronic trip unit — it draws its operating energy from the current transformers around the phase conductors, so no auxiliary supply is needed for the protection functions. The undervoltage release, however, requires a separate 24 V DC supply; factor that into your control transformer sizing and fuse protection.
Lifecycle and sourcing posture
Sourcing is handled on a quoted-to-order basis against an RFQ. Availability and current pricing are confirmed at the time of quotation through independent distribution. Volume purchases or blanket-order agreements can be structured; lead time varies with factory backlog and should be requested at quote time.