What this MCCB is and what it does
The Siemens 3VA2140-7HM36-0AA0 is a SENTRON molded case circuit breaker (MCCB) rated for 40 A continuous current on a 3-pole line-protection design. It carries an insulation voltage rating of 800 V and delivers a breaking capacity of 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 3.7 kA at 690 V — so it handles high-fault-current panels at the lower distribution voltages common in North American and European industrial plants, while the 690 V figure covers the reduced duty at higher line voltages.
Thermal performance and derating
The continuous current rating holds flat at 40 A from 40 °C all the way up to 70 °C ambient — no derating needed across the full operating temperature range of -25 °C to 70 °C. That simplifies panel design in warm enclosures or near heat sources. Power loss is 1.6 W maximum at rated load.
Ground-fault monitoring and physical fit
This MCCB includes summation-current ground-fault monitoring on the L-conductor — it measures the vector sum of phase currents to detect leakage to ground, which is useful for personnel protection and equipment protection in ungrounded or resistance-grounded systems. The unit measures 105 mm wide, 181 mm high, and 86 mm deep, fitting standard SENTRON panel cutouts and busbar systems. Storage range is -40 °C to 80 °C.