Difference between ECDIS, ENC & SENC.

ECDIS

Electronic Chart Display and Information System (ECDIS) means a navigation information system which, with adequate back-up arrangements, can be accepted as complying with the up-to-date chart required by regulations V/19 and V/27 of the SOLAS1974 Convention, as amended, by displaying selected information from a system
electronic navigational chart with positional information from navigation sensors to assist the mariner in route planning and route monitoring, and if required display additional navigation-related information.

ENC

Electronic Navigational Chart (ENC) means the database, standardized as to content, structure and format, issued for use with ECDIS by or on the authority of a Government, authorized Hydrographic Office or other relevant government institution, and conform to IHO standards. The ENC contains all the chart information necessary for safe navigation
and may contain supplementary information in addition to that contained in the paper chart (e.g. sailing directions) which may be considered necessary for safe navigation.

SENC

System Electronic Navigational Chart (SENC) means a database, in the manufacturer’s internal ECDIS format, resulting from the lossless transformation of the entire ENC contents and its updates. It is this database that is accessed by ECDIS for display and other navigational functions, and is equivalent to an up-to-date paper chart. The SENC may also contain information added by the mariner and information from other sources.

Ref: Resolution MSC. 232(82) circular