aluminum wiring vs copper

Status
Not open for further replies.
M

mannyb

Senior Member
Location
Florida
Occupation
Electrician
Customer wants to use aluminum wiring for all feeders on his project for his busimess to save on cost. He asked me was it better to use aluminum vs copper. I told him honestly I never thought about ever using aluminum.I dont really think about saving customer money when installing wire. I just think about how can I do this per NEC and good craftmsnship. The aluminum wire got me thinking. If properly installed whats wrong with using aluminum wiring?
 
Little Bill said:
What does the POCO use?
I have to laugh every time someone insists on copper wire, copper bus, etc. then the POCO comes along and runs Al wire!
Click to expand...
I had a small local poco that was also the AHJ require copper, even though they connected with aluminum! My helper at the time bought a double wide, and we wired the service with aluminum like millions of other trailer services. POCO inspector came out and turned it down saying it had to be copper, that they required it.
 
mannyb said:
Customer wants to use aluminum wiring for all feeders on his project for his busimess to save on cost. He asked me was it better to use aluminum vs copper. I told him honestly I never thought about ever using aluminum.I dont really think about saving customer money when installing wire. I just think about how can I do this per NEC and good craftmsnship. The aluminum wire got me thinking. If properly installed whats wrong with using aluminum wiring?
Click to expand...
The only feeders I personally would run in Aluminum is SER Muliwire and that would be for residential, For a commercial business I would install copper throughout my conduit system, Copper has better conductive properties and doesn't typically require a graphite compound at the termination points to assure heating doesn't get out of hand, Aluminum expands and contracts much more requiring connection to be tightened more often due to the heat of high current flow. Besides the conductors are sized up increasing conduit sizes as well, all due to the needed surface area of a less conductive material. But that's me ..
 
If you want to use aluminum just use all crimp on terminals, that eliminates all of the problems associated with aluminum terminations. Yes they're more labor intensive but you're already saving a ton of money on the cost of the wire.
 
infinity said:
If you want to use aluminum just use all crimp on terminals, that eliminates all of the problems associated with aluminum terminations. Yes they're more labor intensive but you're already saving a ton of money on the cost of the wire.
Click to expand...

(y) Ive never really liked many mechanical terminations. IMO a system with aluminum conductors and crimped terminations a higher quality system than copper with mechanical.
 
We use aluminum for:
Residential and commercial 125 amp and up.
Industrial / municipal 200Amp and up.

infinity said:
If you want to use aluminum just use all crimp on terminals, that eliminates all of the problems associated with aluminum terminations. Yes they're more labor intensive but you're already saving a ton of money on the cost of the wire.
Click to expand...
Good idea.
What kind of crimps do you use? Most plug in residential/commercial breakers/loadecnters would require a ferrule crimp.
 
tortuga said:
We use aluminum for:
Residential and commercial 125 amp and up.
Industrial / municipal 200Amp and up.


Good idea.
What kind of crimps do you use? Most plug in residential/commercial breakers/loadecnters would require a ferrule crimp.
Click to expand...
I would follow the guidelines you've mentioned. For small conductors mechanical lugs peoperly torqued would be fine. I was thinking of larger conductors in a commercial building where there would be a substantial savings in using large aluminum conductors.
 
Thoughts, using aluminum requires:
  • a little training
  • the correct tools
  • the correct connectors
  • two AWG steps larger conductors (14AWG copper to 12AWG aluminum)
 
Something else to factor in to your calculations is that as circuit ampacity goes up, the 'amps per circular mil' goes down, meaning that it requires more conductor material to carry a given total number of amps for larger circuits.

This is one of the main benefits of using parallel conductors for large ampacity circuits.

The relevance here is that for small circuits the cost difference in the conductor material is only a small part of the costs, whereas for large circuits it is a major factor.

My guess is that running a 15A circuit using 12ga aluminium would be more expensive than running it using 14ga copper, simply because of the common availability of materials.

But for a 100A feeder of any length(remember the OP asked about feeders), I am sure the balance changes to favor aluminium.

-Jon
 
Mostly Improper installations gave aluminum a bad name. Also due to ease of damage on smaller sizes such as #12 and #10. Generally feeders are relatively problem free if installed correctly. Most installs that I have seen fail, were improperly installed, such as lugging a copper wire under the same lug. Very common in rural areas with mobile homes, the copper well pump wire is lugged under the same load lugs as the feeder, sometimes to a disconnect, sometimes not.....
 
hillbilly1 said:
Mostly Improper installations gave aluminum a bad name. Also due to ease of damage on smaller sizes such as #12 and #10. Generally feeders are relatively problem free if installed correctly. Most installs that I have seen fail, were improperly installed, such as lugging a copper wire under the same lug. Very common in rural areas with mobile homes, the copper well pump wire is lugged under the same load lugs as the feeder, sometimes to a disconnect, sometimes not.....
Click to expand...

Try to find a transformer which is NOT aluminum windings. Or a utility power line. Conversely ever seen a motor without copper windings (static not rotor)? Nuff said. Nothing wrong with aluminum when used properly.
 
Speedskater said:
Thoughts, using aluminum requires:
  • a little training
  • the correct tools
  • the correct connectors
  • two AWG steps larger conductors (14AWG copper to 12AWG aluminum)
Click to expand...
I don't see copper as being any different than AL for your first two. Regarding the third, 99.9% of connectors and lugs are dual rated. Four, true but AL is always compact stranded so it isn't that much larger than CU, also the AL is lighter for the same ampacity.
 
mannyb said:
..He asked me was it better to use aluminum vs copper...
Click to expand...
Copper Thieves

They follow commercial solar-array installers in my area. Any outdoor raceway rings the dinner bell.
Copper thieves are like sharks, biting into all raceways, but spit out bad taste of aluminum bones.
 
Well being in the electrical preventive maintenance (PM) business we find that the creep characteristic under pressure between aluminum and copper wire is different. It is greater with aluminum than with copper and we see evidence of this during the torquing of cable lug and bus connections. This fact not only makes the installation critical but the importance of continual PM being performed on the equipment down the road.
Some interesting Info:
https://www.carsondunlop.com/training/resources/the-true-story-behind-aluminum-wiring-part-one/

https://www.carsondunlop.com/training/resources/the-true-story-behind-aluminum-wiring-part-two/
 
Status
Not open for further replies.
Top