What this MCCB carries on the nameplate
The Siemens 3VA1150-6EF36-0CA0 is a SENTRON molded case circuit breaker (MCCB) rated 50 A at 40 °C ambient, three-pole, designed for line protection. Its interrupting capacity reaches 220 kA at 240 V AC, 154 kA at 415 V, 121 kA at 440 V, and holds 17 kA at 500 V and 690 V — meaning it can clear high-fault currents on a 240 V secondary bus without cascading upstream breakers. The rated insulation voltage is 800 V, so it is suitable for 480/277 V or 600 V distribution panels with headroom to spare.
Thermal derating and the 50 A frame
This breaker holds 50 A continuously from 40 °C through 50 °C ambient. At 55 °C it derates to 49 A, at 60 °C to 48 A, at 65 °C to 46 A, and at 70 °C to 45 A. The maximum power loss at rated current is 17.1 W. If the panel ambient runs above 50 °C, size the load at the derated figure — the TM240 thermal-magnetic trip unit will follow that curve.
Undervoltage release and auxiliary release design
The 3VA1150-6EF36-0CA0 ships with an undervoltage release (UVR) as the auxiliary release. That means the breaker trips automatically when supply voltage drops below a threshold — standard for safety circuits where a loss of control voltage must open the main contacts. There is no ground-fault monitoring module on this variant, and no communication function. The trip indicator is absent, so a remote status signal will need an auxiliary contact block added separately.
Panel fit and mounting dimensions
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep. It mounts on a DIN rail or directly to a backplate via the SENTRON mounting base. The 3-pole footprint matches the standard 3VA frame spacing, so a panel laid out for a 3VA1110 or 3VA1112 will accept this unit without re-drilling — verify the lug kit and terminal spread if replacing a different brand.
Lifecycle and sourcing posture
The lifecycle stage is marked current, meaning Siemens still lists this order code as an active catalog number. No last-time-buy or phase-out notice is attached to this variant. For BOM planning, the part is sourced and quoted to order against an RFQ through independent distribution; availability and current pricing are confirmed at quote time.