Corona-free Switchgear Design?

[FaradayFF]

Hi,
What are the advantages of corona-free switchgear assembly or other equipment? That is something that some vendors are starting to advertise, not sure what is the practical benefit of this feature if the equipment is located indoors..

Has anyone specified this in the past?
Thank you,
EE

 

[paulengr]

Doesn’t make a lot of sense. If you have corona discharge (partial discharge) you have insulation breaking down. If it’s not corona free, it’s self destructing and either the vendor or installer screwed up.

 

[Jraef]

Maybe it means it was made in a factory where all of the workers were tested for coronavirus?

In all seriousness though, corona testing of switchgear only applies to anything ABOVE 15kV class. So is that what you are referring to? Because stating that LV or MV up to 15kV switchgear is "corona free" is like saying that potato chips are "gluten free" (they never had gluten to begin with... ); it sounds like a marketing gimmick.

 

[petersonra]

Perhaps they sprayed it with chloroquine.

 

[Sahib]

A few years ago I had issue with 22kV indoor switchgear due to corona discharges. Tracking damages on the polymer insulators. The switchgear continued to operate. It was found the swirchgear cubicle heater was not operating being the cause of corona discharges.