Scott Precision's Electrical Resistance wires are specially developed alloy wires which combine the characteristics of a consistent heating effect with excellent corrosion prevention.
Alloys suitable for use from the lowest temperatures up to 1200°C are available. They are manufactured to wire gauges, such as American Wire Gauge (AWG) or Standard Wire Gauge (SWG), metric or imperial diameters or, more commonly, to the particular linear resistance required by you for your component in ohm/m or ohm/foot.
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Totally flexible solutions with
any order or sample size
From small, one off samples to large, quality controlled orders, Scott Precision Wire offer the best, not only in quality production but with ongoing technical support all backed up with a strong supply chain, huge stock and multiple years of experience.
stringent mechanical wire testing services
Mechanical tests are also carried out to confirm the wire has been annealed to the correct mechanical strength, elongation or hardness.
Some raw material batches are tested several hundreds of times, starting as a two-tonne delivery and finishing as 5kg reels, so when we say "Wire end-to-end” we can be sure we mean it.
The increasing use of resistance wires in automotive applications for both emissions controls and comfort heating means that being able to manufacture and maintain records in a manner suitable for supply into this industry is a real strength.
resistance wire inspection regime
Scott Precision Wire can also supply the wire ‘hard drawn’ and, for some sizes, with a lubricated finish. If you require a more specific mechanical yield, elongation or tensile strength range these can also be produced and tested in our laboratory.
The repeated heating up and cooling down resistance wires are subject to during use imparts thermal stresses into the wire. Whilst the alloy combinations have been developed over many years, and ensuring they have low-temperature coefficients of linear expansion has been a key design influence, minimising these stresses will improve longevity.
In cases where it is difficult to replace the heating elements, in underfloor heating cables, for instance, bunching or stranding the conductors will help.
Our stranded and bunched conductors are subject to the same inspection regime as solid wires, so whatever the format, the conductor will exhibit the same consistency.
Totally flexible solutions with
any order or sample size
From small, one off samples to large, quality controlled orders, Scotts Precision Wire offer the best, not only in quality production but with ongoing technical support all backed up with a strong supply chain, huge stock and multiple years of experience.
resistance wire faq's
Resistance wire is used to make electrical resistors, which are used to control the amount of current in a circuit. Alongside controlling the amount of current in a circuit, resistance wire can generate heat, since its increased resistance to the flow of electricity produces heat. It is often used as a heating element for domestic goods and industrial purposes because of this; for example, resistance wire is used for toasters and hair dryers, as well as for heated car seats in coiled form.
Resistance wire is typically made from an alloy material, such as nichrome (nickel and chromium), or copper, manganese and nickel.
Low-resistance wire has low resistance to an electrical current. This type of wire is a good conductor of electricity, allowing the electricity to pass through it without much opposition. Because low-resistance wires allow an electrical current to pass through, more power arrives at its intended destination, rather than being lost as heat.
Resistance is affected by the length of a wire, area of cross-section (or thickness), and resistivity; therefore, typically a low-resistance wire may feature a thicker area of cross-section, shorter length, and low resistivity.
Unlike low-resistance wire, high-resistance wire has greater opposition to an electrical current. Its resistance to this current generates heat, so is often used for heating elements in applications where heat is desirable. A high-resistance wire will generally not be a conductive wire and can be made from nichrome (nickel and chromium) or nickel and iron.
Surprisingly, the best conductor of electricity is pure silver. However, since this material is so impractical to use as a conductor, copper and aluminium are more commonly associated with conductors of electricity. Copper and aluminium are both widely available and affordable, and durable, making them suitable for many applications.
Resistance and resistivity are closely associated; however, they are individual properties. Resistance encompasses the properties of the material wire (this includes the length of the wire, area of cross-section, and resistivity), whilst resistivity is the opposition to an electric current offered by the material. This is measured in ohms-metres and will remain consistent regardless of the length or area of the cross-section.
Resistance is also directly proportional to resistivity, meaning the greater the resistivity, the greater the resistance of the wire.
The resistance of a wire (R) can be calculated by multiplying resistivity (ρ) by the sum of length (L) divided by the area of the cross-section (A). This will look like R = ρ (L / A). However, online calculators are available to calculate the resistance of a wire directly.
The resistance of a wire is affected by the area of cross-section, or thickness. If the thickness of the wire changes, so will the resistance – this relationship is moreover inversely proportional. Therefore, the thinner the area of cross-section, the greater the resistance, since the wire carries fewer electrons with which to conduct the electrical current.
Insulated resistance wire features a coat or enamel of insulation, typically a thermoplastic such as polyester, through which an electrical current cannot pass. An insulated resistance wire is not designed to generate heat as a heating element but does make for a good resistor because of its increased insulation.
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