Tables: Electrical values.
 
  • Specific electrical resistance ρ and conductance for conductors at 20°C
  • Specific electrical resistance ρ of insulators
  • Electrical coefficients of temperature α at 20°C
  • Dielectric constant εr
  • Series of electrochemical tension .

Industry instrumentation : Units and conversion tables for process control

Español -Tablas : Valores eléctricos .

  

Specific electrical resistance ρ and conductance for conductors at 20°C

Material
 ρ [ Ωmm2 ]

m
Material
 ρ [ Ωmm2 ]

m
Strained steel 1 1 Brass Ms63 0,071 14
Ingot steel 0,13 7,7 Magnesium 0,0435 23
Pure steel 0,10 10 Manganese 0,423 2,37
Aluminum 0,0278 36 Mercury 0,941 1,063
Antimony 0,417 2,4 Nickel 0,087 11,5
Cadmium 0,076 13,1 Niquelín 0,5 2,0
Coal 40 0,025 Gold 0,0222 45
Copper 0,0172 58 Silver 0,016 62,5
Constantan 0,48 2,08 Artificial Silver 0,369 2,71
Chromium-Ni-Fe 0,10 10 Platinum 0,111 9
Tin 0,12 8,3 Lead 0,208 4,8
Graphite 8,00 0,125 Wolfram 0,059 17
Brass Ms58 0,059 17 Zinc 0,061 16,5

Specific electrical resistance ρ of insulators
Material  ρ [ Ω cm ] Material  ρ [ Ω cm ]
Paraffin oil 1018 Marble 1014
Water of sea 106 Mica 1017
Distilled water 109 Pure paraffin 1022
Artificial amber 1024 Porcelain 1020
Bakelite 1016 Humid earth 108
Hard rubber 1016 Glass 1017

Electrical coefficients of temperature α at 20°C
Material α 20° [1/°C] Material α 20° [1/°C]
Fused steel +0,00660 Manganio  +0,00001
Aluminum   +0,00390  Mercury   +0,00090
Coal -0,00030 Nickel   +0,00400
Copper   +0,00380 Niquelín  +0,00023
Constantan  -0,00003 Silver   +0,00377
Tin   +0,00420 Artificial silver +0,00070
Graphite   -0,00020 Platinum +0,00390
Brass   +0,00150  Zinc  +0,00370

Dielectric constant εr
Insulating material  εr

A/cm

 Insulating material  εr

A/cm
Colza oil 2,2 Hard rubber 2,8
Paraffin oil 2,2 Vulcanized rubber   2,7
Oil by root 3    
Castor oil 4,7 Lacquer 3,5
Mineral oil for transformer 2,2 Seal sealing wax 4,3
Olive oil 3 Marble 4
Vegetal oil for transformer 2,5 Mica  8
Water 80 Micanita  5
Air 1 Paper 2,3
Insulation for cables 2,5 Kitchen paper 4,2
Insulation for high tension wires 4,2 Paraffin 2 , 2
Insulation for telephone wires  1,5 Paraffin 2,2
Asbestos - rubber  4 Slate 4
Bakelite    2,7 Porcelain   4,4
Cardboard   4,5 Fabric   4
Quartz   4,5 Terpentina  2,2
Ebonite   2,5 Glass 5
Volcanic fiber 2,5  Glass (Zeiss) 1,6

 

Series of electrochemical tension .

(Difference of tensions referred to Hydrogen electrode )

Material Volts Material Volts
Steel -0,44 Mercury +0,85
Aluminum -1,69 Nickel  -0,25
Cadmium -0,40  Gold  +1,38 
Calcium -2, 76 Silver  +0,80
Calio -2, 92 Platinum  +0,46
Cobalt  -0,29 Lead  -0,13
Copper  +0,35 Sodium -2,71
Chromium  -0,56 Wolfram  -0,58
Tin  -0,14 Zinc  -0,76
Hydrogen  0,00    
Magnesium  -2,34    
Manganese  -1,10