How many types of earthing

Question

Accepted Answer

There are several types of earthing used in electrical engineering.

The most common types of earthing are:
- TN-S system: separate neutral and protective earth
- TN-C system: combined neutral and protective earth
- TN-C-S system: combination of TN-S and TN-C systems
- TT system: separate earth for each electrical installation
- IT system: no direct connection to earth, relies on insulation monitoring
Other types include:
- TN-R system: neutral is directly earthed at source
- TN-B system: neutral is earthed at multiple points
- TN-C-S-PEN system: combination of TN-C-S and TN-S systems with a combined neutral and protective earth
- IT-TN system: combination of IT and TN systems
- IT-TT system: combination of IT and TT systems

Accepted Answer

Five types of earthing system.

TN- S,

TN-C-S,

TN-C,

TT,

IT

Where,

T= Earth, N= Neutral, C= Combined, S= Separate I= Isolated

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