Where is it recommended to connect the ground wire for a building electrical system?

The recommended practice for connecting the ground wire in a building electrical system is to ensure it is bonded to the grounding system in a manner that effectively protects against electrical faults and provides a clear path for fault currents. Connecting the ground wire to a cold water pipe is one method that has historically been used, especially in older buildings, because water pipes are often metallic and provide a reliable path to ground.

However, it is also important to ensure that the connection to the water pipe is secure and meets local electrical codes. Over time, plumbing systems may not be reliable for grounding due to potential insulation or corrosion, leading to interruptions in the grounding system. To improve reliability, modern electrical systems often recommend using a grounding rod driven into the ground as a best practice for grounding, as it provides a dedicated path for fault currents directly to the earth.

Choosing a cold water pipe is contextually significant because it emphasizes practical grounding techniques that have been used for years, although current standards typically prioritize grounding rods or other more effective grounding methods.