What this breaker is and what the ratings mean for your panel
The Siemens 3VA1020-4ED32-0AA0-ZD00 is a 3-pole IEC frame 100 circuit breaker from the 3VA1 series, rated for 20 A continuous current with a fixed thermal-magnetic trip unit (TM210). Its interrupting capacity hits 36 kA at 415 V — that is the Icu, the maximum fault current it can safely clear once. For a panel feeding a tire-curing press or a DC power OEM line, that 36 kA rating means the breaker holds up to the steam-side fault levels without upstream coordination headaches. The short-circuit protection is fixed at Ii = 16 × In, so the magnetic trip fires at 320 A. That is a deliberate choice: high inrush loads (motors, transformers, DC bus capacitors) pass through without nuisance trips, but a hard fault still clears fast. The overload protection Ir is fixed at 20 A — no adjustment range on this variant.