Enamelled Resistance Wire

 

Enamelled Wires

 

The enamelled resistance wires supplied by Scott Precision Wire are coated with a dual coat modified polyester enamel system which combines the excellent physical and electrical properties of a modified polyester base coat with the added chemical resistance, surface toughness, smoothness and high thermal rating of a polyamide-imide polymer topcoat. The combination of these two high quality resins produces a coating that has outstanding abrasion resistance, flexibility, chemical resistance, burnout and thermal shock resistance and dielectric strength. These properties, coupled with careful selection and processing of the wire, produces an enamelled wire which meets the exacting requirements of the electrofusion industry.

The standard coating type is Grade 2, however Grade 1 and Grade 3 are also available.           

 

When applied to copper wire and used in conventional applications the enamel system meets the requirements of BS EN 60317-13, the primary properties being:

 

Thermal Properties

 

212°C            Temperature Index                                 

340°C            Cut-through Temperature                    

 

Chemical Resistance

 

No softening apparent after 24 hours immersion at room temperature in:           

 

Ethyl alcohol

Toluene

Ethyl Acetate,

Trichloroethylene,

Solvent Naphtha,

            Mild Alkali (1% KOH),

),          Mild Acid (5% H2SO4

            IEC Solvent Blend,

            Alcohol/Toluene (70:30),

            Xylene. 

Whilst users need to carry out trials to determine the suitability of the enamelled resistance wire in their particular application Scott Precision Wire’s enamelled resistance wires have been proven in a variety of electrofusion fittings by various manufacturers. 

Dimensions and Breakdown voltage

Values for intermediate sizes are taken as those of the next largest diameter.The table below summarises the minimum increase due the enamel and the breakdown voltages for the most common range of wire diameters.   

Minimum Increase and Minimum Breakdown VoltageTable 1          -            

Conductor Diameter

mm

Minimum Increase Due to the Insulation

mm

Minimum Breakdown Voltage

(r.m.s. value)

V

 

Grade 1

Grade 2

Grade 3

Grade 1

Grade 2

Grade 3

0.25

0.017

0.032

0.048

2100

3900

5500

0.28

0.018

0.033

0.050

2200

4000

5800

0.315

0.019

0.035

0.053

2200

4100

6100

0.355

0.020

0.038

0.057

2300

4300

6400

0.40

0.021

0.040

0.060

2300

4400

6600

0.45

0.022

0.042

0.064

2300

4400

6800

0.50

0.024

0.045

0.067

2400

4600

7000

0.56

0.025

0.047

0.071

2500

4600

7100

0.63

0.027

0.050

0.075

2600

4800

7100

0.71

0.028

0.053

0.080

2600

4800

7200

0.80

0.030

0.056

0.085

2600

4900

7400

0.90

0.032

0.060

0.090

2700

5000

7600

1.00

0.034

0.063

0.095

2700

5000

7600

1.12

0.034

0.065

0.098

2700

5000

7600

1.25

0.035

0.067

0.100

2700

5000

7600

1.40

0.036

0.069

0.103

2700

5000

7600

1.60

0.038

0.071

0.107

2700

5000

7600

1.80

0.039

0.073

0.110

2700

5000

7600

2.00

0.040

0.075

0.113

2700

5000

7600

For intermediate conductor diameters the figure of the next largest diameter shall be taken

Information contained within this technical data sheet is based upon the general experience of Scott Precision Wire Ltd and is believed to be correct at the time of issue. 

No warranty is given or is to be implied from  the details above. 

Customers are advised to carry out independent tests in order to determine the suitability of any Scott Precision Wire Ltd product for an application.

  

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