What it is and what it does
The Siemens 3VA2116-5HN42-0AA0 is a SENTRON 3VA2 molded case circuit breaker (MCCB) rated for 160 A continuous current across the full ambient range from 40 °C to 70 °C — no derating curve to chase on a hot panel day. It's a 4-pole, line-protection design with an ETU350 electronic trip unit, built for main feeder or large subfeed duty in commercial and industrial switchboards. The interrupting ratings tell you where it'll hold fault current without blowing apart: 187 kA at 240 VAC, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 3.7 kA at 690 V. That 187 kA number at 240 V is the one that matters for high-fault panels close to a transformer — most MCCBs top out well below that.
Panel fit and integration
Dimensions are 140 mm wide, 181 mm tall, and 86 mm deep — a standard 4-pole MCCB footprint that fits most distribution panelboards and switchboard cubicles. Front IP40 protection keeps dust and accidental contact out while allowing heat dissipation through the vents. The ETU350 trip unit is field-adjustable for long-time, short-time, instantaneous, and ground-fault pickup — no need to swap the whole breaker for a coordination change.
What the ETU350 means for selectivity
The ETU350 electronic trip unit gives you adjustable I²t curves and zone-selective interlocking (ZSI) capability. That means you can coordinate this breaker with downstream feeders to clear a fault close to the load without taking the whole bus down — critical for a production line where a nuisance trip on a subfeed stops a whole cell.