Term

Graphical Symbol

in full

simplified

Coils

general

or

air-cored coil

or

air-cored coil with two tappings

or

iron core

iron core and air gap

iron dust core

iron-core choke

or

Transformers

single-phase transformer with iron core (if errors cannot be made, the core need not be drawn)

single-phase transformer with iron-core and 3 windings (core not represented)

three-phase transformer in star-star connection (core not represented)

three-phase transformer, star-delta connection

three-phase autotransformer in star connection