All COPPER conductors supplied by Nexans have a purity guaranteed not less than 99.8%. Virtually all are drawn from copper rod made at the Nexans factory in Montreal East, from copper supplied by Noranda’s adjacent copper refinery. Common sizes of soft bare conductors are readily available from stock.

Copper conductors may be TINNED to resist corrosion or to make soldering easier.

In COMPACT conductors each layer of wires in the conductor is compacted so that all the wires are segment shaped leaving no air spaces visible between the wires. This reduces the conductor diameter approximately 9% to 10%. Compact conductors are standard in large size Teck and most medium voltage power cable.

COMPRESSED has the outer layer of wires in a stranded conductor smoothed, thereby reducing the diameter approximately 3%. Compressed conductor is used in all building wire.

Used in small flexible conductors, BUNCHED strand is a group of very fine wires twisted together in a common direction: not concentrically. ROPE strands are assemblies of bunch-stranded members that are used in very flexible cables, such as welding cable. These strands are expensive, and used only where essential.

Conductors can be stranded in several different ways. The original was ROUND strand, in which a single solid center wire has other solid wires wrapped around it in layers.

Copper is most commonly supplied in soft (drawn) TEMPER. It is easy to pull into conduits, and to terminate. Medium hard and hard are seldom used, except where strength is needed such as going from pole-to-pole along streets, or as power supply conductors for streetcars or overhead cranes.

The ALLOY used for many years has been EC grade (or alloy 1350). In recent years the need to improve aluminum's handling characteristics led to the introduction of the 8000 series of alloys (known as ACM). Alloy 8030 ACM is now standard in all Nexans aluminum conductor building wire products. Aluminum has approximately 61% of the conductivity of copper, therefore a larger sized conductor must be used to carry the same current as copper. Many conductors for use overhead and directly buried are stocked. Aluminum RA90 Corflex, RWU90, RW90 and ACWU90 building wire is readily available.

STRANDING

Aluminum STRANDING is the same as for copper, except that it is not suitable for very fine flexible conductors, since the individual fine aluminum wires composing the strand are susceptible to breakage during manufacture and use.

TEMPER

The use of aluminum conductors is NOT as simple as copper. Aluminum (and its alloys) quickly form an oxide ‘coat’ and this can lead to faulty ‘hot’ connections. There are some UNIQUE INSTALLATION REQUIREMENTS for aluminum. The conductor must be wire brushed to remove the oxide, then immediately covered in a suitable inhibitor (such as Penetrox). Lugs and terminals must be designed for use with aluminum to ensure good conductivity, and evenly spread pressure to avoid cold flow. Before using aluminum conductors it is wise to obtain specific advice on proper installation methods. Aluminum can save some money on the initial cable purchase, but requires more care in installation and if improperly installed can cause serious problems. ACM aluminum alloys help to eliminate some of these problems with aluminum conductors but TIME, KNOWLEDGE and CARE are ESSENTIAL.