Side-by-side reference

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Compare the meaning, drawing context and source references of two entries. A similar graphic or shared abbreviation does not establish equivalence.

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SDFSB

Symbols

Station DC feeder selectivity boundary

Shows the protective-device relationship considered when assigning downstream DC fault isolation. A station battery system supplies protection, control and other assigned DC loads through a documented charger and distribution arrangement. Charger output, battery contribution and load distribution are related but separately monitored paths.

Drawing use: Schematic
Application: Metering & protection
Reference family: Manufacturer

A distinction that matters

Selectivity requires a DC protection assessment. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.

Full reference

SDDS

Symbols

Station DC dual-bus segregation

Keeps two separately assigned station DC distribution buses identifiable across their outgoing circuits. A station battery system supplies protection, control and other assigned DC loads through a documented charger and distribution arrangement. Charger output, battery contribution and load distribution are related but separately monitored paths.

Drawing use: Schematic
Application: Metering & protection
Reference family: Manufacturer

A distinction that matters

Shared battery or charger dependencies must be shown. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.

Full reference

Follow the full entry for source drawings and the appropriate standard or selected product. Equipment previews show a manufacturer drawing where available, otherwise a 3D thumbnail.