What it is and what it does
The Siemens 3VA2063-5HN36-0AC0 is a SENTRON 3VA2 molded case circuit breaker, three poles, built for line protection in distribution panels. It's rated for 63 A continuous current (Iu) across the ambient range from 40 °C to 50 °C, with a slight derate as you climb past 55 °C — at 70 °C it still carries 53.55 A, so it handles warm enclosures without a drama. The interrupting capacity is the headline here: 187 kA at 240 V, 121 kA at 415 V and 440 V, 79 kA at 500 V, and 3.4 kA at 690 V. That kind of headroom means it'll clear a bolted fault upstream of a motor starter or a feeder without the arc flash energy getting out of hand — you can coordinate selectivity downstream without worrying about the main breaker letting go first. It carries an ETU350 electronic trip unit — that's the adjustable thermal-magnetic replacement that gives you long-time, short-time, and instantaneous pickup settings. No undervoltage release, no ground-fault monitoring, no communication module on this variant. The auxiliary contacts are two built-in switches (HQ type), so you get status feedback without an add-on block.
Panel fit and mounting
Dimensions are 105 mm wide, 181 mm tall, 86 mm deep. That 86 mm depth is the critical number for enclosure depth — it'll fit a standard 200 mm deep wall-mount panel with room for the gland plate and wiring gutters. The 105 mm width means it takes three 18 mm pole spaces on the DIN rail, same footprint as the rest of the 3VA2 family. Front protection is IP40, so it's fine inside a clean panel but don't mount it where washdown spray or dust gets in. The terminals accept the usual lug sizes for 63 A; no special busbar adapters needed for the SENTRON range.
What the ratings mean for the buyer
The 187 kA at 240 V interrupting capacity isn't just a number on a sticker — it means this breaker can safely clear a fault up to that level without welding its contacts or venting arc plasma into the panel. For a 63 A feeder, that's way above typical utility fault currents (usually 10–25 kA at the service entrance), so you've got selectivity headroom to let downstream breakers trip first. The 121 kA at 415 V is still massive for a 63 A frame — it'll handle any industrial distribution board short of a direct transformer secondary.