A current transformer (CT) supplies a representation of current to measuring instruments and protective relays. In a substation, the associated secondary wiring forms part of the connection between the CT and the equipment that uses its signal.
Where the console box fits
A CT console box is described in the site's existing CT material as an interface between equipment and the control-room panel. A separate discussion of substation wiring refers to cables between a CT console box and a control relay panel in an air-insulated substation. These descriptions establish the context for the term; they do not define every console box or its internal arrangement.
Measurement and safety context
Protective equipment can use CT secondary current as an input. For example, the Siemens 7SR242 transformer protection relay manual describes measuring its line CT inputs and using the resulting quantities for that relay’s protection functions. This is an example of a device using CT signals, not a description of every console box.
CT secondary circuits require particular care: the 7SR242 manual warns that the secondary circuit of a live CT must not be open-circuited because injury or equipment damage can result. Work on a specific installation requires the applicable equipment instructions and qualified personnel; this overview is not a wiring procedure.
Names and boundaries
Substation documents also use terms such as CT terminal box and marshalling box. The NIMI electrician training material lists their wiring as separate subjects. Its transformer discussion describes auxiliary wiring from accessories to a marshalling box. These references do not establish that a CT console box, a CT terminal box and a marshalling box are interchangeable names for the same equipment.
The equipment identification and circuit documentation for a particular installation provide the context for understanding its arrangement. This overview does not specify connections or work procedures.
Sources
CT measurement and protection context and the distinction between training topics are based on the NIMI Electrician (Power Distribution), second-year theory and the Siemens 7SR242 technical manual, PDF pages 17 and 33. The console-box terminology is also described in the site's current transformer overview and three-phase control wiring article.