What is the TN-C System?

What is the TN-C System?

TN-C System Definition

TN-C system has both the neutral and protective functions combined in a single conductor throughout the system. This conductor is called PEN (protective earth neutral). The consumer’s earthing terminal is directly connected to this conductor.

TN-C System Advantages

• Reduces the number of conductors required for supply, which lowers the cost and complexity of wiring.

• Provides a low impedance path for fault currents, which ensures a fast operation of protective devices

TN-C System Disadvantages

• Creates a risk of electric shock if there is a break in the PEN conductor or if it comes into contact with live parts due to insulation failure.

• Causes unwanted currents to flow in metal pipes or structures that are connected to PEN at different points, which can result in corrosion or interference.

• Requires special precautions for connecting appliances with exposed metal parts that may be accessible simultaneously with other earthed metal parts.