MP for Tinned Copper Wire

[ohms]

Hi guys,

Melting point of Tin = 203
Melting point of Cu = 1083
For earthing calculation purpose, when considering tinned-copper wire, can we take 203 degree as the maximum allowable temperature, being on safe side as the MP of Cu is high enough to sustain this temperature.

Thanks for helpful hints.

 

[itsmoked]

This is uninsulated right?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[ohms]

yes

 

[Marmite]

Depending on your particular application and the nature of the earthing system, there may be local or national standards applicable which would tell you the maximum allowable temperature rise. In the UK for example, if you are talking about substation earthing then EA Tech Spec 41-24 applies which states 405 deg C for 3 seconds based on a 30 deg C ambient. I'm sure there will be a similar ANSI spec. You would need to be more specific about the application to get an accurate and meaningful answer.
Regards
Marmite

 

[jghrist]

If you need the tin coating to protect against galvanic corrosion of buried steel structures or lead sheaths, then you should limit the temperature to the melting point of tin. If corrosion is not a concern, you don't need the tin plating anyway and it doesn't matter if it melts off, so use the melting point of copper.