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  1. How are the transformer, consumer's side and the generator earthed in a T-T Earthing system?
  2. I seem to understand that the generator and its frame should be earthed separately; The neutral of the generator is earthed at the site while its frame is connected to an earth bar in the Main Low Voltage Panel (MLVP). Is that correct?
  3. For the transformer, I understand that the supply company provides earthing for the neutral of the transformer at the site. Is that correct?
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  1. How are the transformer, consumer's side and the generator earthed in a T-T Earthing system?

All will have earth rods driven into the ground. Earth rods are typically steel or copper rods driven into the sub soil.

  1. I seem to understand that the generator and its frame should be earthed separately; The neutral of the generator is earthed at the site while its frame is connected to an earth bar in the Main Low Voltage Panel (MLVP). Is that correct?

The three phases & neutral exit the generator station as cables. Chassis metal is earth grounded so that faulty insulation that touches the metal could not energise parts of the assembly that a person could touch. The resistance of this path to ground governs the fault current. Another advantage is that the return current path (electrically noisy) is separated from the earth, minimising interference.

The ground rod at the generator is connected to the other ground rods through the earth - this forms a (high impedance) path for the fault current. The main advantage of this setup is that if the cable is damaged, there is a still a fault path to ground though the local earthing rod.

The local earthing rod will have an earth bar in a distribution box as you say.

  1. For the transformer, I understand that the supply company provides earthing for the neutral of the transformer at the site. Is that correct?

Usually yes. The star point of the transformer will be earthed locally.

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