What the ratings mean for your panel
The Siemens SENTRON 3VA2140-7KQ32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling. The 330 kA interrupting capacity at 240 V and 242 kA at 415 V means this breaker handles high-fault scenarios common in industrial distribution, safely clearing a short-circuit without upstream devices needing to trip. The ETU860 electronic trip unit gives you adjustable time-current curves (tr min 0.5 s to tr max 25 s, tsd max 0.5 s) so you can coordinate selectively downstream. Mounts in a standard panel footprint: 181 mm tall, 105 mm wide, 86 mm deep. The front face carries IP40 protection — fine for a clean indoor panel; keep it out of washdown zones. Communication function is built in (no external module required for basic integration), and the ground-fault monitoring works via summation current formation on the L-conductor — useful for detecting leakage in ungrounded or high-resistance-grounded systems.
Sizing and selectivity notes
The 40 A rating holds at every ambient point from 40 °C to 70 °C — no thermal derating curve to calculate. That simplifies panel design in warm enclosures or near other heat sources. The ETU860 release lets you set the short-time delay (tsd) up to 0.5 s, which gives downstream breakers time to clear a fault before this one opens, preserving uptime on unaffected feeders. Rated insulation voltage is 800 V. The interrupting capacity drops to 3.8 kA at 690 V.