Integrator's spec recap — 3VA2040-5KP42-0AA0
The Siemens SENTRON 3VA2040-5KP42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for 40 A continuous current, carrying the ETU850 electronic trip unit. Its interrupting capacity hits 187 kA at 240 VAC and 121 kA at 415/440 VAC — numbers that govern the available fault current the installation can handle without upstream coordination issues. The breaker includes a communication function (likely for remote monitoring or trip indication via the ETU850's optional modules), though no specific protocol is listed in the base spec. Front IP40 protection suits panel-mount applications; no IP rating on the sides means the enclosure must keep dust and moisture out.
Breaking capacity by voltage — selectivity headroom
The 3VA2040-5KP42-0AA0 delivers 187 kA at 240 V, 121 kA at 415/440 V, 75.6 kA at 500 V, and 3 kA at 690 V. That steep drop above 500 V is typical for an MCCB with a 40 A frame — the arc extinction limits at higher line-to-line voltages. For a 480 V wye system (277 V line-to-neutral), the 187 kA rating at 240 V is not directly applicable; the 75.6 kA at 500 V is the relevant figure. Coordination studies should use the 500 V column for 480 V panels.
Mounting and integration — panel fit
Dimensions: 86 mm deep, 140 mm wide, 181 mm high. The ETU850 trip unit is field-adjustable for long-time, short-time, instantaneous, and ground-fault pickup. The communication function occupies the accessory slot on the front.