How to connect the ground wire and the power wire in the distribution box

Connect the power ground wire to the PE (protective earth) bar inside the distribution box using a properly sized yellow-green insulated copper wire, ensuring a secure and reliable connection.

Step-by-

Step Connection

Locate the Grounding Bar (PE Bar) Open the distribution box and identify the grounding bar, often marked with "PE" or a grounding symbol. This is the designated point for all grounding connections inside the box. Select the Correct Ground Wire Use a yellow-green insulated copper wire with a cross-sectional area that meets local electrical codes (typically at least 6 mm² outside the US or 10 AWG in the US).

This wire ensures good conductivity and provides a visual warning for safety. Prepare the Wire Strip the insulation from the end of the ground wire for a sufficient length to make a secure connection. Avoid damaging the copper strands while stripping.

Connect to the PE Bar Insert the stripped end of the ground wire into the terminal of the PE bar and tighten the screw firmly with a screwdriver. Ensure the connection is secure and cannot loosen over time. Ground Electrical Components If there are other electrical components inside the distribution box that require grounding, connect them to the PE bar using additional copper wires.

This ensures all equipment shares a common ground for safety. Verify Grounding Check that the ground wire is properly connected to the main grounding electrode system, such as a grounding rod, buried metal water pipe, or concrete-encased electrode. The resistance between the distribution box and the grounding point should be low (typically