160 A MCCB with 187 kA interrupting capacity at 240 V
The Siemens SENTRON 3VA1140-5EE32-0BM0 is a 3-pole molded case circuit breaker rated for a continuous current Iu of 160 A, with a thermal-magnetic TM240 overcurrent release. Its interrupting capacity reaches 187 kA at 240 V, 121 kA at 415 V, and 76 kA at 440 V — figures that place it in the high-breaking-capacity tier for industrial distribution panels. The 800 V rated insulation voltage (Ui) gives headroom for 480 V and 600 V class systems without series-derating concerns. This is a line-protection version, meaning the TM240 release is calibrated for cable and busbar protection rather than motor or generator circuits. The undervoltage release (UVR) integrated as the auxiliary release trips the breaker when control voltage drops below a threshold — a standard requirement for safety disconnects in emergency-stop chains and for preventing automatic restart after a power loss.
Current derating across the operating range
The 160 A rating holds flat from 40 °C through 50 °C, then derates gradually: 158 A at 55 °C, 155 A at 60 °C, 153 A at 65 °C, and 150 A at 70 °C. This thermal curve is typical for a TM release with a 40 °C calibration reference. In a panel with ambient above 50 °C — a common condition in non-climate-controlled enclosures near ovens or in direct sun — the effective ampacity drops by roughly 6% at 70 °C. Factor this into the load schedule rather than relying on the nameplate 160 A.
Physical fit and panel integration
The breaker measures 130 mm in height and 3 inches in width, fitting standard 3-pole MCCB mounting footprints in SENTRON distribution boards and third-party enclosures with adjustable DIN-rail or bolt-on adapters. Front IP40 protection means the breaker face is sealed against tools and solid objects over 1 mm, but the terminals remain exposed for wiring — standard for panelboard installation where the enclosure door provides the overall IP rating.