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Current limitation 
The term "current limitation" refers to the action of limiting the peak value of the prospective impulse short-circuit current ip to a lower let-through current iD. The compact design of the breakers has been made possible by their excellent current limiting capabilities. In the event of a short circuit, the molded case circuit breaker significantly reduces the magnitude of let-through current, i.e. it reduces the current loading of downstream equipment (lower thermal load, fewer dynamic forces). The level of let-through energy is also reduced to a considerable extent.
The 3VA UL molded case circuit breakers are designed as current-limiting molded case circuit breakers; however, they do not have "current limiting certification" according to UL 489 yet. A version of 3VA with higher interrupting rating capacity and Current Limiting certification from UL is in development.
Let-through characteristics can be found in Siemens Industry Online Support (SIOS) on the following link. You can search for a particular breaker and filter results by "Characteristic" in the "Entry Type" field.
https://support.industry.siemens.com/cs/products?mfn=ps&lc=en-US
