What this MCCB carries and where it fits
The Siemens SENTRON 3VA1112-5EF36-0AG0 is a 3-pole molded case circuit breaker (MCCB) rated 125 A at 40 °C with a TM240 thermal-magnetic release, designed for line protection in distribution panels. Its 187 kA interrupting capacity at 240 V AC and 121 kA at 415 V AC mean it can clear high-fault currents without upstream cascading — sized for main or large feeder breakers in industrial switchboards. The 800 V rated insulation voltage and operating range from -25 °C to 70 °C suit it for unconditioned electrical rooms and outdoor enclosures.
Breaking capacity across voltage levels
This MCCB delivers 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V (–). The steep drop above 500 V is typical for a compact-frame MCCB — at 690 V the 17 kA rating still covers most industrial loads but requires verifying the available fault current at that voltage. The TM240 release provides thermal and magnetic trip curves matched to cable and transformer protection.
Current derating and thermal budget
Rated 125 A continuously from 40 °C through 50 °C (–). Above 50 °C it derates: 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, 114 A at 70 °C (–). Maximum power loss is 28.1 W — factor that into enclosure ventilation, especially when grouping multiple breakers. The 70 mm depth and 76.2 mm width fit standard MCCB panel cutouts; the 130 mm height leaves room for auxiliary wiring above the line terminals.
Built-in auxiliary switching and trip indication
Factory-fitted with 1 auxiliary switch and 1 trip alarm switch — no separate order for signal contacts. The trip indicator gives local visual status. No undervoltage release, no ground-fault monitoring, and no communication function on this variant; those are available on other 3VA family order codes if the BOM requires them.