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#173320 - 01/07/08 12:56 PM distance correction factor
dcdec Offline
New Member

Registered: 01/07/08
Posts: 1
Loc: ontario, canada
I'm looking for distance correction factor for 500 Kcmil aluminum table- d3 (6) states that distance and current follow a pattern factor of 10 does this mean from 4/0 I have to go each wire size up by 10x distance and current at this cables max. nominal amperage which would 185 Amp (doesnt exist on table, 160 or 200) and this is not for a residential service , it will be 600v delta.
look forward to reply, thanks in advance

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#173355 - 01/08/08 04:13 AM Re: distance correction factor [Re: dcdec]
mr_electrician Offline
Member

Registered: 06/22/07
Posts: 106
Loc: London, Ontario
I believe what note 6 is saying is that when a current factor is increased by 10, then the max distance of that cable is decreased by 10. As well note six is used when you cannot find a value from the charts. Also, 600V will have less voltage drop than you think. A good rule of thumb is for every 100 feet of conductor, go up one size. But to be acurate, just use the example in note 9 but insert 600 V as the divisor or you will get the wrong answer. If that still doesn't help you, just call the inspector.
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#173991 - 01/24/08 05:42 PM Re: distance correction factor [Re: mr_electrician]
RobbieD Offline
Member

Registered: 02/23/03
Posts: 238
Loc: Canada
Because Table D3 is based on single phase, make sure that after you find out your answer, multiply the distance by 1.15 due to the fact that you said you are using 3 phase.

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