Temperature termination 69 to 75 degrees cel

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Jpflex

Jpflex

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I have 2 large 3 phase 480 volt motors needing to be wired up individually with SOOW cord but the NEC stops at #2 AWG at 80 amperes max before temperature derating adjustment.

The FLC ampacity of the motors require 124 amperes and wires are sized 1.25% of this for continuous duty = 155 ampere wire

Apparently SOOW is made larger than #2 but I can’t find a chart anywhere meeting or exceeding 155 amperes?

Where can I find specs for larger SOOW than #2? Thanks
 

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Also since most SOOW cord is rated for 90 degrees Celsius insulation, how could I determine its ampacity for 60 or 75 degree terminations, so I don’t melt component terminations?
 
Jpflex said:
I have 2 large 3 phase 480 volt motors needing to be wired up individually with SOOW cord but the NEC stops at #2 AWG at 80 amperes max before temperature derating adjustment.

The FLC ampacity of the motors require 124 amperes and wires are sized 1.25% of this for continuous duty = 155 ampere wire

Apparently SOOW is made larger than #2 but I can’t find a chart anywhere meeting or exceeding 155 amperes?

Where can I find specs for larger SOOW than #2? Thanks
Click to expand...
Table 400.4 only permits that type of cord up to 2AWG. There are other flexible power cables in that table that can be used with some of them going up to 500lcmil.
 
Does the equipment have some sort of special markings? Usually it doesn't.
With 110.14(C)(1) forcing you to be based on Table 310.15(B)(16) as appropriately modified by 310.15(B)(7), you are not able to use those other cable tables. Granted, I am being a bit of a troublemaker, but 110.14 is hard to avoid.

110.14(C)(1) Equipment Provisions. The determination of termination provisions of equipment shall be based on 110.14(C)(1)(a) or (C)(1)(b). Unless the equipment is listed and marked otherwise, conductor ampacities used in determining equipment termination provisions shall be based on Table 310.15(B)(16) as appropriately modified by 310.15(B)(7).
Click to expand...
 
Besoeker3 said:
Just a bit of a digression related this topic. You guys use degC for electrical measures but not for weather. I wonder why ?
Click to expand...

Most all engineering ratings are in C.
Kind of like petrol in the UK being sold by the litre, but cars are rated in miles per gallon. And I think that’s an Imperial gallon.
 
don_resqcapt19 said:
Table 400.4 only permits that type of cord up to 2AWG. There are other flexible power cables in that table that can be used with some of them going up to 500lcmil.
Click to expand...

So you cannot use larger than SOOW #2 for bigger motors? Where would the nec code on this be?
 
ron said:
Does the equipment have some sort of special markings? Usually it doesn't.
With 110.14(C)(1) forcing you to be based on Table 310.15(B)(16) as appropriately modified by 310.15(B)(7), you are not able to use those other cable tables. Granted, I am being a bit of a troublemaker, but 110.14 is hard to avoid.
Click to expand...
Except for cords and cables to be based on table 400..
 
Jpflex said:
Except for cords and cables to be based on table 400..
Click to expand...
There is nothing in the code that says you can use ampacities other than those found in Table 310.16 at terminations, unless the termination is listed and marked for use with conductors having other ampacities. There is no blanket permission to use the ampacities in Article 400 for terminations.
 
tom baker said:
interesting. But motors we use hP instead of kW
Now soft drinks are in liter bottles
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Yes, we use litre bottles too but, oddly, we still use pints when you go to the pub. There is a group that has campaigned long and hard for reals - the CAMRA . As it happens my wife and I usually have have a 250 ml glass of wine there. - in a cool 10C one........:)
 
don_resqcapt19 said:
There is nothing in the code that says you can use ampacities other than those found in Table 310.16 at terminations, unless the termination is listed and marked for use with conductors having other ampacities. There is no blanket permission to use the ampacities in Article 400 for terminations.
Click to expand...

You have to be in article 430 for motors

430.6 ampacity and motor determinations

The size of conductors supplying EQUIPMENT covered by article 430 shall be selected from tables 310.15....WHERE FLEXIBLE CORD IS USED the size of the conductors shall be selected with table 400.5.
 
Jpflex said:
You have to be in article 430 for motors

430.6 ampacity and motor determinations

The size of conductors supplying EQUIPMENT covered by article 430 shall be selected from tables 310.15....WHERE FLEXIBLE CORD IS USED the size of the conductors shall be selected with table 400.5.
Click to expand...
There is nothing in 430 that modifies the rule in 110.14. There is not even a provision in the code that would permit a rule in one Chapter 1-4 article to modify a requirement in another Chapter 1-4 article. There should be, but 90.3 does not say that.
 
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