What it is and what it does
The Siemens 3VA1080-3ED42-0JA0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries an 80 A rating at 40 °C ambient, holds that current through 50 °C, then derates to 78 A at 55 °C, 77 A at 60 °C, 75 A at 65 °C, and 74 A at 70 °C — so in a warm enclosure you lose about 6 A off the nameplate by the time you hit 70 °C. The 4-pole construction handles three-phase-plus-neutral or three-phase with a switched neutral, common for North American and European panel builds.
Breaking capacity across voltages
Interrupting rating is voltage-dependent: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 7.5 kA at both 500 V and 690 V. That 7.5 kA at 690 V is the weak point — if your fault current at 690 V exceeds that, this breaker won't clear it safely. For most 400 V-class distribution (415 V nominal), 52.5 kA gives plenty of headroom for a typical 25–36 kA SCCR panel. The rated insulation voltage is 800 V, so the internal clearances are designed for 690 V systems.
Overcurrent release and auxiliary release
The overcurrent release is a TM210 — thermal-magnetic, fixed trip. The auxiliary release is a shunt trip (STL) for remote tripping via control voltage. No undervoltage release, no ground-fault monitoring, no communication function. The supplied basic switch is order code 3VA10803ED420AA0.
Physical fit and environment
Dimensions: 130 mm height, 101.6 mm width, 70 mm depth. That 101.6 mm width is exactly 4 inches — standard MCCB footprint for a 4-pole frame in a panel. Operating temperature range is -25 °C to 70 °C; storage from -40 °C to 80 °C. Maximum power loss is 19.2 W, so factor that into your enclosure thermal calculation if you're stacking several breakers.