This just came from Mike Holt “We’d like to share with you this paper written by Bob Yanniello, Division Engineer Manager at Eaton Electrical Inc.”
http://www.eaton.com/ecm/groups/public/@pub/@electrical/documents/content/1143077762513.pdf
This just came from Mike Holt “We’d like to share with you this paper written by Bob Yanniello, Division Engineer Manager at Eaton Electrical Inc.”
http://www.eaton.com/ecm/groups/public/@pub/@electrical/documents/content/1143077762513.pdf
Perfect Article…While it did not expand to explain the AA 8000 series and why it changed the conductor world back in 1972…clearly at this point in time the decision from CU to AL is purely just a choice now…more like a design choice ultimately.
However, I will add something to that article. The terminations that are clearly marked as acceptable for AL conductors have already been evaluated for that termination. They are designed to gel ok with the anticipated thermal expansion or contraction aspect of the termination. This is why they must be evaluated for the actual conductor termination as part of the terminations listing.
It is very true that AL and CU expand and contract based on thermal differences but this has been accounted for as part of a properly installed, torqued and selected system that accepts AL or CU terminations. Think of it like you do with the nameplate for an HVAC system, Maximum Overcurrent Protective Device and Minimum Circuit Ampacity…the label has determined the course of action…you just follow the label. This is the same concept for the use of AL conductors (or CU conductors) when it comes to terminations.
Both CU and AL are wonderful conductors…when sized correctly, torqued correctly and used correctly you will have long reliable life from both of them.
Thanks for the info Nice to read it all