CEI EN 61148

This International Standard is applicable to the terminal
markings for the main circuits of valve device stacks and
assemblies, and of integrated conversion equipment. The terminal
markings refer to stacks, assemblies and equipment comprising
semiconductor valve devices.

NOTE 1 Terminal markings for auxiliary circuits, including gate
terminals and non-integrated conversion equipment with separate
manufacturing of its components and their interconnection only
after installation on site, are not considered in this
standard.

For such equipment the relevant standards, if any, for the
individual components apply.

Gate terminal markings are given in 6.3.

Terminal markings for other circuits such as protective
conductor are not considered in this standard.

The object of this standard is to specify a logical alphanumeric
marking system for the identification of the external main
terminals of the main power circuits in a stack, valve device
assembly or integrated conversion equipment, which is applicable
for the purpose of reference in circuit diagrams, catalogues,
descriptions, and information exchange and storage.

In the case of stacks and assemblies, alphanumeric terminal
marking systems are indicated for those converter connections which
are the most important and most commonly used ones.

Terminal marking systems making use of graphic symbols or
identifying colours are not considered in this standard.

NOTE 2 The terminals of auxiliary circuits should be marked such
that they may be clearly identified.