Siemens 3VA1040-3ED32-0CH0 — SENTRON MCCB, 40 A, Line Protection
The Siemens 3VA1040-3ED32-0CH0 is a SENTRON molded case circuit breaker (MCCB) rated for 40 A continuous current (Iu) at 40 °C, with a TM210 thermal-magnetic release. It's a 3-pole unit built for line protection — meaning it sits upstream protecting a feeder or distribution bus, not a specific motor or load with integrated overloads. The interrupting ratings climb to 75.6 kA at 240 V and 52.5 kA at 415 V, so it handles high-fault-current scenarios common in industrial switchgear. This breaker includes an undervoltage release (UVR) as the auxiliary release, plus a 2-auxiliary-switch + 1-trip-alarm-switch HQ contact block. The trip indicator is present, and the front face carries IP40 protection — fine for a clean indoor panel, but not for washdown areas. No communication function, no phase failure detection, and no ground fault monitoring are built in; this is a straightforward thermal-magnetic MCCB without electronic trip unit extras.
Current Rating and Thermal Derating
The 40 A rating holds flat from 40 °C through 50 °C. Above that, it derates: 38.4 A at 55 °C, 37.6 A at 60 °C, 36.8 A at 65 °C, and 36 A at 70 °C. If your panel ambient runs hot — say, next to a drive cabinet or in a non-climate-controlled enclosure — the 36 A at 70 °C figure is the one to size against, not the 40 A headline. The rated insulation voltage is 800 V, and the mechanical endurance is 15,000 cycles.
Interrupting Ratings Across Voltages
The interrupting capacity varies sharply with system voltage: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 7.5 kA at 690 V. That 7.5 kA at 690 V is the limiting case — if your distribution is 690 V, this breaker's SCCR is modest. For a 415 V panel with typical transformer impedance, 52.5 kA covers most service-entrance and sub-feed applications. The TM210 release is a fixed thermal-magnetic design; no electronic adjustment or zone-selective interlocking here.
Physical Fit and Panel Integration
Dimensions: 70 mm deep, 76.2 mm wide, 130 mm tall. That 76.2 mm width is a standard 3-pole MCCB footprint — it drops into the same panel cutout as other 3VA 3-pole frames. The IP40 front protection means it's rated for indoor panel mounting only; no outdoor or washdown exposure. The undervoltage release (UVR) is wired separately; if your control voltage is missing or drops, the breaker trips open — common for safety circuits or emergency-stop chains where loss of control power should kill the load.