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NEC Figure 250.1.

The grounded neutral conductor provides a current return path for anything utilizing a neutral supplied from the secondary side of the transformer.

All neutral conductors are grounded conductors but not all grounded conductors are neutrals.

Each grounded conductor shall terminate within the panelboard in an individual terminal that is not also used for another conductor.

Many raceway types qualify as an equipment grounding conductor.

The main bonding jumper is connecting the grounded circuit conductor, the equipment grounding conductor busbar, and the supply-side bonding jumper to the service enclosure.

The supply-side bonding jumper ensures the required electrical conductivity between metal parts required to be electrically connected.

Notice the paint scraped off from the pipe before the grounding clamp was installed. Not a bad idea to paint the surface after the clamp is installed to avoid future rust.

Reconnecting a grounded conductor to ground on the load side of the service disconnect is prohibited unless another section in Article 250 allows it.

Many line side connections, such as this PV system, terminate in an enclosure that is not considered a service disconnect.

NEC 250.28(A) permits aluminum and copper-clad aluminum main bonding jumpers which aligns with Table 250.102(C)(1).

Multiple generators of the same type connected in parallel.

According to 250.53(A)(3), if multiple rod, pipe, or plate electrodes are installed to meet the requirements of 250.53(A)(2), they must be at least 6 feet apart.

Pool rebar is not to be used as the grounding electrode system for the electric service.

Relying on the rebar to interconnect the water pipe to the service as in the image is a code violation.

What type of PVC should be used to protect these grounding electrode conductors? Schedule 40 or schedule 80?

Common hot gutter type service installation with the grounding electrode conductors connected to the exposed copper grounding busbar.

Cable armor is similar to armored cable type AC, but there is little space between the armor and the conductor inside.

NEC Table 250.66.

Interior metal water piping used to extend a GEC connection to an electrode must be electrically continuous with a metal underground water pipe electrode.

The hold-down bolts can be connected to the concrete-encased electrode by welding, exothermic welding, the usual steel tie wires, or other approved means.

The rebar stub up on the right emerged from the concrete stem wall, not the earth (soil).

The grounding or bonding conductor shall be connected to the grounding electrode by exothermic welding, listed lugs, listed pressure connectors, listed clamps, or other listed means.

Similar code language is located in 250.86 for other than service raceways.

Similar code language is located in 250.80 for service raceways.

Section 250.94 allows two different methods for bonding communications systems.

The further the two dissimilar metals are to each other on the chart means more difference in galvanic potential.

NEC Table 250.102(C)(1) is used for sizing the grounded conductor, main bonding jumper, system bonding jumper, and supply-side bonding jumper for alternating-current systems.

NEC Table 250.102(C)(1).

NEC 250.8 requires a listed clamp when bonding the gas piping system.

Metal enclosures are permitted to be used to connect bonding jumpers or equipment grounding conductors, or both, together to become a part of an effective ground-fault current path.

FMC cannot be larger than trade size 1 &frac14; inch if using the raceway as the equipment grounding conductor.

Unless an exception applies, equipment grounding conductors 6 AWG and smaller are required to be green their entire length.

NEC Table 250.122

All equipment grounding conductors in the gutter must be joined together.

An equipment grounding conductor passing through the box without a splice is not required to be joined inside the box to others that are spliced in the box.

These are utility grade DC solar heat generators that direct sunlight into a Stirling engine.

Some grounding and bonding fittings that are listed for use in wet and corrosive environments are marked &ldquo;direct burial&rdquo; or &ldquo;DB&rdquo; as in the image.

Copper grids are permitted for equipotential bonding of perimeter surfaces adjacent to a pool.