What this MCCB carries — and what it means on the panel
This 3VA1040-4ED32-0BH0 is a SENTRON molded case circuit breaker rated 40 A continuous current (Iu) with a TM210 thermal-magnetic release — so it handles overloads and short-circuits in one unit, no external relay needed. The 3-pole design covers three-phase line protection. Interrupting capacity sits at 121 kA at 240 V AC and 75.6 kA at 415 V AC, giving solid SCCR headroom for most industrial distribution panels without cascading upstream. It ships with an undervoltage release (UVR) already fitted — that's the coil that drops the breaker if supply voltage falls below a threshold, common for safety disconnects on conveyor or machine-tool circuits. The auxiliary contact block provides two form-C aux switches plus a separate trip alarm contact, so the PLC or SCADA knows the breaker state without adding a separate module. Thermal derating is flat from 40 °C to 50 °C — still 40 A — then drops to 38.4 A at 55 °C and 36 A at 70 °C. If the panel ambient runs hot, that 36 A floor is the number to design against, not the nameplate 40 A.
Lifecycle and sourcing posture
The mechanical endurance rating of 15 000 operations is typical for a 40 A MCCB in panel service — not a daily-switching contactor, but fine for infrequent disconnect or backup protection. The IP40 front protection means it's suitable for enclosed panel mounting, not open washdown zones.
Dimensions and panel fit
Width 76.2 mm (roughly 3 inches of DIN rail space), depth 70 mm, height 130 mm. That's a standard SENTRON 3VA footprint — drops into the same cutout as other 3VA 3-pole frames. The 70 mm depth means it clears most 200 mm deep enclosures with room for wiring gutters.
Interrupting capacity at a glance
The 121 kA at 240 V is the headline number, but the 75.6 kA at 415 V is the one that matters for 400 V class panels — that's well above typical utility fault levels in most industrial plants. At 690 V it still holds 11.9 kA, enough for secondary-side protection on 690 V step-down transformers.