What it is and what it does
The Siemens 3VA1020-2ED36-0HH0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection in distribution panels. It carries 20 A at 40 °C ambient across three poles, with a breaking capacity of 52.5 kA at 240 V — enough to handle high-fault industrial feeds without cascading upstream. The 52.5 kA interrupting rating at 240 V means it safely clears a bolted fault up to that level, protecting downstream wiring and equipment. At 415 V the rating drops to 32 kA; at 690 V it holds at 7.5 kA, reflecting the voltage-dependent arc extinction limits typical of MCCBs.
Key ratings and what they mean for fit
Rated current holds at 20 A from 40 °C up to 55 °C, then derates to 19 A at 60–70 °C. That flat thermal curve means it can sit in a warm panel without losing headroom — useful for enclosures near motors or ovens. Rated insulation voltage is 800 V, so the breaker is suitable for 690 V line-to-line systems common in heavy industrial installations. Maximum power loss is 12 W per pole — a useful figure for thermal management in a multi-breaker enclosure.
Built-in accessories and panel integration
This variant comes with a shunt trip (STL) release and two auxiliary switches plus one trip alarm switch (HQ). The shunt trip allows remote tripping from a PLC or emergency-stop circuit; the auxiliary switches report breaker status back to the control system. Dimensions are 76.2 mm wide, 70 mm deep, 130 mm tall — a 3-pole footprint that fits standard Siemens SENTRON mounting and bus-bar systems. No undervoltage release or ground-fault monitoring on this version.