Aluminum Feeders or copper??

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powerplay

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For a large service, it was unanimous that aluminum feeders would work fine and cost alot less. From the splitter to the two 200amp panel feeding an agricultural lighting load, would there be any issues from using aluminum?...should copper be used for the final short length to the panel? I have someone that seems convinced that the used core and coil ballasts are burning out because of some voltage drop from the last leg that is causing problems with a few lights.
 
moble home feeder cable

moble home feeder cable

what am I missing? A 200 amp RES service, aluminum, Table 310.15(b)(6) says 4/0 phase conductors....Grounded conductor = 230.42 (c) says grounded conductor shall not be less than the min size in 250.24 (c)...250.24(c)(1) says shall not be smaller than the GEC specified in 250.66.... So in 250.66 the largest ungrounded conductor for my 200 amp service is a 4/0 making the size of my grounded conductor a #2. Why is it that all the moble home service feeder cables have a 2/0 neutral.
 
gary w hill said:
....So in 250.66 the largest ungrounded conductor for my 200 amp service is a 4/0 making the size of my grounded conductor a #2. Why is it that all the moble home service feeder cables have a 2/0 neutral.
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250.66 has the minimum size required. Depending on the actual calculated neutral demand/load, it may be possible to need a larger size.

Most mobile homes' calculated neutral loads would be satisfactorily served by a 2/0 neutral, hence the reason why manufacturers offer that in a bundled size of underground cabling.

FWIW, we use a 1/0 neutral in our mobile home feeders ....
 
ActionDave said:
If you have one voice of dissent then the consensus is not unanimous. That being said, I will plant myself firmly in the camp of the majority.

There is nothing wrong with AL feeders.
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The opinions from qualified electricians "was" unanimous... the opinion comes from post installation discussion, based on a person with no electrical education explaining his opinion to his buddies what he thought was going on without my presence or asking me the specifics of the installation. Based on his feedback, the conclusion drawn was that they needed to change the aluminum from the splitter to the panel nippled 2" away and that it needed to be oversized. The load is 80% of panel rating, and the wires are 250KCMIL aluminum. I was wondering if that last connection would have made a difference if copper.... sounds like properly sized no difference would have been made?
 
The concern is always terminations with AL. With the newer (out for many years) AL blends, the termination is not as much of a concern. Most people would be okay with AL if the end to be terminated was cleaned/brushed and no-ox applied. Be sure to use a lug that is rated for AL or CU/AL
 
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