Material Combinations and Dimensions - AWS310 - AWS310-SITE - AWS430 - FOC201 - RME111 - RWCC - RWS200

Grounding and Lightning Protection in Vaisala Outdoor Installations Technical Reference

Document code
M211786EN
Revision
B
Language
English
Product
AWS310
AWS310-SITE
AWS430
FOC201
RME111
RWCC
RWS200
Document type
User guide

Make sure to use galvanically compatible metals in lightning protection system components and surface materials on which the components are mounted. For example, do not connect copper to aluminum. For more information, see Table 1.

CAUTION Do not use together metals that are not galvanically compatible. Bad matching accelerates their corrosion in the presence of moisture.

With aluminum conductors, use only connection devices designed for aluminum. Make sure to use the right fastening torque.

Examples of metals to use with copper
  • Nickel
  • Brass
  • Tin
  • Lead
  • Stainless steel
  • Monel (nickel–copper alloy)
Examples of metals to use with aluminum
  • Magnesium
  • Zinc
  • Galvanized steel
  • Stainless steel
  • Lead
  • Wrought iron
  • Galvalume (an aluminum-coated sheet steel product)

Table 1 lists generic guidance on materials and their use in different environments and conditions. Consider the conditions and requirements of individual sites when deciding on materials and their use.

Table 1. LPS Materials and Conditions of Use (IEC 62305-3 Ed 2)
Material Use Corrosion
In Open Air In Earth In Concrete Resistance Increased by May be destroyed by Galvanic Coupling with
Copper Solid Solid Solid Good in many environments Sulphur compounds
Stranded Stranded Stranded Organic materials
As coating As coating
Hot galvanized steel123 Solid Solid Solid Acceptable in air, in concrete, and in benign soil High chlorides content Copper
Stranded 4 Stranded 4
Steel with electro-deposited copper Solid Solid Solid Good in many environments Sulphur compounds
Stainless steel Solid Solid Solid Good in many environments High chlorides content
Stranded Stranded Stranded
Aluminum Solid Unsuitable Unsuitable Good in atmospheres containing low concentration of sulphur and chloride Alkaline solutions Copper
Stranded
Lead 5 Solid Solid Unsuitable Good in atmospheres with high concentration of sulphates Acid soils Copper
As coating As coating Stainless steel
1 Galvanized steel may be corroded in clay soil or moist soil.
2 Galvanized steel in concrete should not extend into the soil due to possible corrosion of the steel just outside the concrete.
3 Galvanized steel in contact with reinforcement steel in concrete should not be used in coastal areas where there may be salt in the ground water.
4 Stranded conductors are more vulnerable to corrosion than solid conductors. Stranded conductors are also vulnerable where they enter or exit earth/concrete positions. This is the reason why stranded galvanized steel is not recommended in earth.
5 Use of lead in the earth is often banned or restricted due to environmental concerns.