IG-123-EN version 11; 23/07/2021
6
General description
General instructions
cpg
.0: GIS medium-voltage switchgear,
gas insulated, up to 40.5 kV,
in accordance with IEC Standard
Gas tank
This is a sealed compartment, made of stainless steel and
sealed for life, which houses the switching and breaking
switchgear, with gas as the insulating medium.
Depending on the function the cubicle was designed for, it
may contain some of the following components inside:
• Disconnector.
• Earthing switch.
• Internal busbar and connections.
• Vacuum circuit-breaker.
• Switch-disconnector.
• Fuse holders.
Connection to the busbar is possible via top bushings.
Connection to the medium-voltage cables is made with the
bottom and/or side bushings.
The
gas pressure is tested
in each cubicle by means of a
temperature-compensated pressure switch with a volt-
free contact, allowing it to be used as a remote alarm or
blocking/trip for the position.
Figure 1.2.
Example of bushing position in gas tank (1)
Busbar compartment
The busbar compartment, designed to withstand an
internal arc inside (optional), meeting the criteria of Annex
A of Standard IEC 62271-200, class IAC: AFL/AFLR, is located
at the top of the cubicle, separate from the gas tank. It is
made from sheet metal, offering the degree of protection
necessary for the connecting device.
It comprises a fully assembled, tested unit, separated by
phases, by way of earthed metal plates, with solid, screened
insulation, earthed through an earth collector flat bar
specific to the compartment.
Toroidal-core current transformers and/or plug-in voltage
transformers can also be installed, thus avoiding the need
for metering cubicles.
Figure 1.3.
Phase segregation in the busbar (optional)
Summary of Contents for velatia cpg.0
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