What this breaker is and what it carries
The Siemens 3VA1120-4EF36-0CC0 is a 3VA1 IEC frame 160 molded-case circuit breaker with a 36 kA breaking capacity at 415 V AC — class S, meaning it sits in the middle of the 3VA1 breaking-capability tiers, suited for distribution panels where fault levels are moderate but not trivial. It is a 3-pole unit with a TM240 thermal-magnetic trip unit, rated In = 20 A, with overload protection adjustable from 14 A to 20 A and short-circuit protection set at 8 to 16 times In.
The TM240 trip unit provides thermal (overload) and magnetic (short-circuit) protection: the thermal element tracks heating from sustained overcurrents, adjustable via the Ir dial between 14 A and 20 A, while the magnetic element reacts instantaneously to currents between 8× and 16× In (160 A to 320 A).
Integration and deployment context
The clamp terminals accept copper or aluminium conductors without lug crimping — speeds up panel wiring on distribution boards.