Siemens 5SN1NG20A Circuit Breaker

Siemens 5SN1NG20A is a 1-pole circuit breaker from the 5SN1-NG family, rated for 20 A, designed for Siemens NG-series low-voltage panels and enclosures. This single-pole device provides overcurrent protection for branch circuits in standard AC electrical distributions and is intended for use in Siemens NG-frame panels that accept 5SN1-type breakers. The part is interchangeably listed as 5SN1NG20A or 5SN1-NG20A across supplier catalogs, confirming its NG frame designation and current rating. In practical terms, it is used to protect lighting and general power circuits in commercial, industrial, and some residential installations that rely on Siemens NG-series distribution equipment, and it appears in both Siemens catalogs and third-party marketplaces as a direct replacement within NG-series installations.