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View Full Version : Bonding and grounding what's the difference


kirkg1431
Jan 24, 2011, 04:25 PM
Bonding vs. grounding

DrDavros
Jan 24, 2011, 04:38 PM
It depends on the context. You can bond two metal surfaces together via springy fingers around the edge etc, or via a woven wire strap, but that doesn't mean that the entire structure is connected to the earth.

It depends on the application or situation you are involved with. In terms of electrical safety, some countries have power supplies which have an earth reference, and it is important to connect all electrical devices with metal exteriors to the earth point of the building through a low resistance path. The earth point is often a long metal rod sunk into the earth.

If you are describing lightning protection of a building, then it is important to connect the lightning rod to earth via a low impedance path (thick conductive metal with minimal kinks and bends) to ensure that a lightning strike will discharge to earth without going through conductive elements of the building (including reinforcing rods in concrete) or electrical equipment or people.

If you can describe more the situation, it would be possible to be more specific.
D.

stanfortyman
Jan 24, 2011, 05:01 PM
bonding vs. groundingThis question cannot be answered as asked. The subject is far too deep and complex.

Ask again with more detail as to the direction of your question.

donf
Jan 25, 2011, 03:14 PM
At a very high level, grounding is the electrical circuit that carries away electrical discharges to earth.

Bonding is the connection of all metal parts so that they are held at the same reference level.

Think of it this way. Ground can carry a fault current fast enough to ensure that a circuit breaker will trip. This will open the breaker and kill the circuit before there is a fire or a dead person on the floor.

Bonding, for example, makes sure that a metal sink is held at the same level of potential as that of the metal on the stove.

If this potential (voltage) were allowed to at different levels, a current would flow. The person in the middle would be shocked, the person behind her will get a concussion from the flown pot because she got the shock.