Line protection breaker with ETU320 — what the ratings mean for fit
The Siemens SENTRON 3VA2110-6HL32-0KC0 is a 3-pole molded case circuit breaker rated for line protection duty, carrying 100 A continuous current (Iu) across the 40 °C to 50 °C band before derating begins at 55 °C (96.25 A) and down to 85 A at 70 °C. That derating curve matters for a panel with elevated ambient — if your enclosure runs above 50 °C, the breaker must be sized up or the load trimmed. Interrupting capacity is the headline: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 5 kA at 690 V. Those figures cover high-fault industrial service — a 242 kA rating at 240 V means it safely clears faults on a large step-down transformer secondary without upstream cascading. At 690 V the 5 kA rating is lower but still adequate for most motor-circuit applications at that voltage level. The overcurrent release is an ETU320 electronic trip unit. It provides adjustable long-time, short-time, and instantaneous protection curves — not a fixed thermal-magnetic. That gives the panel designer flexibility to coordinate with downstream breakers and avoid nuisance trips on inrush. The breaker also includes a shunt trip (STL) for remote opening and two auxiliary switches HQ for status feedback to a PLC or annunciator.
Lifecycle and sourcing reality
Rated insulation voltage is 800 V, and the maximum power loss is 10 W — a modest thermal footprint for a 100 A frame. The part ships with the basic switch assembly 3VA2110-6HL32-0AA0 and the integrated auxiliary trip 3VA9688-0BL33; those subassembly order codes are what you'd reference for replacement internal modules.
Panel integration — mounting and wiring
Dimensions are 86 mm depth, 105 mm width, 181 mm height. The 105 mm width is the standard 4-module MCCB footprint for a 3-pole SENTRON frame — it fits the same DIN-rail or screw-mount pattern as other 3VA2 breakers. The 86 mm depth gives clearance for rear-connected busbars or cable lugs; verify that your enclosure depth exceeds 86 mm plus wiring bend radius. Operating temperature range is -25 °C to 70 °C; storage range -40 °C to 80 °C. The 10 W maximum power loss is the heat that must be removed from the enclosure — factor it into your thermal budget if several breakers are ganged.