What is the advantage (or disadvantage) of rigid alumnium conduit over rigid steel?
Pros:What is the advantage (or disadvantage) of rigid alumnium conduit over rigid steel?
Aluminum conduit should not be installed with direct contact to concrete and cement. Also, aluminum conduit is not recommended to be installed in contact with soil.
Here is a link to one of many conduit and tubing manufactures.
http://www.wheatland.com/electrical-conduit, they have a dowloadable Pdf on one of the active pages.
Wheatland also supplies Rigid Aluminum Conduit (RAC), which provides: extra protection in most corrosive and industrial atmospheres, ease of installation, reduced maintenance costs and a bright, attractive appearance.
And, AL is very expensive.
Cons:
- Slightly more material cost,
One other advantage not yet mentioned is that the aluminum raceway can be a longer run than steel & still provide an effective low impedance ground fault return path.
Thanks for the replies.
I didn't find the PDF you were talking about, but they do sum it up pretty well on the main page:
Do you have any backup for this statement?
I know it's not part of the NEC. The NEC doesn't limit the length of a conduit used as an equipment ground path, either steel or aluminum.
I guess it depends a lot on where you buy it, if they have it in stock, and how much you need. It probably is very expensive if you have to special order a small amount.
RS means shows AL being only about 10% more, with the labor savings being more than 10% for AL.
I was thinking about spec'ing AL for a rooftop run. I may put both AL and RGS in the spec, and let the contractor install whichever he would rather use. For this application, it doesn't sound like either have a great advantage.
See Soares Book On Grounding & Bonding, Chapter 11, Long Conduit Run Designs. Starts on page 204 in the 10th edition & on page 202 in the 11th edition.
Also see this thread:
http://forums.mikeholt.com/showthread.php?t=122232
See Soares Book On Grounding & Bonding, Chapter 11, Long Conduit Run Designs. Starts on page 204 in the 10th edition & on page 202 in the 11th edition.
Also see this thread:
http://forums.mikeholt.com/showthread.php?t=122232