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19 Cards in this Set
- Front
- Back
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Copper Conductors |
Standard for base comparison-100% conductivity Ductility - Good Solderability - Good Corrosion Resistance - Good Oxidation Resistance - Good Weight - 14.25kg(31.4lb)/1000' of #10 @ 20degC Tensile Strength - 250,000 kPa (36,250 psi) |
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Copper/Steel Conductors |
<100% conductivity Ductility - Good Solderability - Good Corrosion Resistance - Good Oxidation Resistance - Good Weight-13.06 kg (28.8lb) / 1000' of #10@20degC Tensile Strength - 380,000 kPa (55,114 psi) Typ. used for aerial, self-supporting drop wire. |
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High-Strength Alloy Conductors |
85% conductivity (typical) Ductility - Best Solderability - Good Corrosion Resistance - Poor Oxidation Resistance - Good Weight - Varies Tensile Strength - 250,000 kPa (79,771 psi) |
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Aluminum Conductors |
61% conductivity (typical) Ductility - Good Solderability - Requires special techniques Corrosion Resistance - Good Oxidation Resistance - Poor Weight-4.32 kg (9.5lb) / 1000' of #10@20degC Tensile Strength - 69,000 kPa (10,000 psi) |
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Solid vs. Stranded Conductors |
Solid - Cheaper, easier to terminate, better transmission performance at high frequencies, lower resistance
Stranded - More flexible, longer flex life, less susceptible to damage during crimp termination processes |
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Composite Conductors (Advantages) |
Advantages - Flexible, lightweight, inexpensive and easy to produce, easily embedded into other materials, low coefficient of expansion
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Composite Conductors (Disadvantages) |
Disadvantages - Poor analog transmission (including high attenuation - esp. over 4kHz), poor digital trans. characteristics, damaged unless in rigid material, inconsistent quality
Not recommended for use with modern telecom networks |
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AWG |
American Wire Gauge |
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Dielectric |
Insulation - Prevents direct contact between conductors and environment/conductors
Extruded polymers are generally used now
Reduces EM coupling between conductors |
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Electrical performance of twisted-pair cables vs. dielectric constant |
Performance is inversely related to the insulation's dielectric constant and dissipation factor |
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PVC |
Polyvinyl chloride - was commonly used for inside plant cables Dielectric Constant (non plenum) - 3.4 Dielectric Constant (plenum) - 3.6 Dissipation Factor (non plenum) - None Dissipation Factor (plenum) - 0.04 |
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PE |
Polyethylene - was commonly used for outside plant (OSP) cables Dielectric Constant - 2.3 Dissipation Factor - None |
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FEP |
Fluorinated ethylene propylene (e.g., Teflon) Dielectric Constant - 2.1 Dissipation Factor - 0.0005 |
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ECTFE |
Ethylene chlorotrifluoroethylene (e.g., Halar) Dielectric Constant - 2.5 Dissipation Factor - 0.01 |
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XL Polyolefin |
Dielectric Constant - 3.8 Dissipation Factor - None |
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Dielectric Constant |
Ratio of capacitance of an insulated conductor to the capacitance of the same conductor uninsulated in the air.
Generally, a low constant is desireable. Constant changes with temp, freq, et al. |
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Dielectric Strength |
Measures maximum voltage an insulation can withstand without breakdown
Voltage / insulation thickness = dielectric strength
High value is preferred
7,500-30,000 V/mm (300-1,200 V/mil) - Typ. range |
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Dissipation Factor |
Relative power loss in insulation due to molecular excitement
High frequency MHz ranges have increased signal loss due to insulating material structure
Low factor is preferable |
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IR |
Insulation Resistance
Insulation's ability to resist the flow of current through it
Typically expressed in Mohm/km or Mohm/1000' |
