What this MCCB does for a 40 A feeder
The Siemens SENTRON 3VA2040-7JQ36-0AA0 is a 3-pole molded case circuit breaker rated for 40 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling. It carries a 330 kA breaking capacity at 240 V, dropping to 242 kA at 415 V and 440 V, then 187 kA at 500 V, and 3 kA at 690 V. That makes it a high-interrupting-capacity feeder breaker for large transformers or bus ties where fault currents are severe.
ETU560 release and ground-fault monitoring
The overcurrent release is an ETU560 electronic trip unit with adjustable long-time pickup and delay (tr from 0.5 to 25) and short-time delay (tsd up to 0.5 s). Ground-fault monitoring uses summation current formation on the L-conductor. Communication function is built in, so this breaker can report status and trip events to a BMS or SCADA system without an add-on module.
Panel fit and environmental limits
Dimensions are 105 mm wide, 181 mm tall, 86 mm deep — standard MCCB footprint for a 3-pole frame in this class. Front protection is IP40, so it handles incidental tool contact but not washdown. Operating range spans -40 °C to 70 °C; storage goes to 80 °C. Power loss is 2.2 W maximum, which keeps heat rise manageable in a crowded enclosure. Latching endurance is rated at 20 000 operations.