Confused about wire gauge for 50A brewrig service

[pickles]

I've been looking for 6/4 SOOW cable for my brewrig thats fed by a 50A GFCI. I just saw a post in another thread with this link. Every reference I've seen state that 6 ga wire is appropriate for 50A yet this one is rated for 65A. Which is correct or are there factors that make both correct?

 

[Sawdustguy]

I am not an electrician but in looking at American Wire Gauge Table it seems as if you will need to go with 4 awg wire.

http://www.powerstream.com/Wire_Size.htm

 

[marzsit]

6 awg so cord will safely handle 50 amps as long as the cord is not enclosed in walls or conduit.

 

[pickles]

Whoa 4ga! So what about the link that claims the 8ga is rated for 65A?

 

[Sawdustguy]

6 awg so cord will safely handle 50 amps as long as the cord is not enclosed in walls or conduit.

Not according to the American Wire Gauge chart.

 

[DoubleXL]

6/3 with ground is good for 50 amp. That is what is used in new homes for heat exchangers that have a 50 amp breaker in them. Most of the time there is a 50 amp and a 30 amp breaker in them and a piece of 6/3 and8/3 is used to supply power to the heat exchanger.

 

[dobeluvr]

it all has to do with the insulation, and diameter of the conductors, table 310.16 of the national electrical code states, not more than 3 conductors in raceway (conduit) or cable is good for 55/65/75 amps depending on the temperature rating of the insulation.

6/3 soow cable could be used, if you run an external ground wire, however to have 2 hots a nuetral and a ground in the same cable, ie 6/4 soow you must examine the nec a little closer. see next post

 

[dobeluvr]

however to be fair, the above reasoning does not take into full consideration art. 310.16 of the national electrical code. As the title of Art 310.16 states "Allowable Ampacities of Insulated Conductors Rated 0 Through 2000 Volts, 60°C Through 90°C (140°F Through 194°F), Not More Than Three Current-Carrying Conductors in Raceway, Cable, or Earth (Directly Buried), Based on Ambient Temperature of 30°C (86°F)", the part you are concerned with is the current-carrying wording. The ground is not considered current carrying therefore you do not need to derate 6/4 soow if one of the wires involved is to be used for grounding purposes.

posted in 2 parts to allow a more thorough thought process, therefore with more consideration of the n.e.c, 6/4 soow wiring is suitable to be used for a hot hot nuetral and ground at 55 amps

 

[pickles]

Ok that makes sense. I'm guessing the link to the 8 ga wire is bs then.

 

[Stickshaker]

You will be fine with 8 gauge. Not only is the ground not a current carrying conductor, but the neutral only carries the unbalanced load between the two hots.

 

[dobeluvr]

http://www.nationalsupplyonline.com/Electrical_Wire.html

The above post is correct when it states that the neutral only carries the unbalanced load current. This makes it a current carrying conductor. However the above link lists different soow sizes and their ratings, as based on nec, in an easy to read format. It states 8 awg soow good to a max 40 amps...As you may never actually run full load it may work fine.....it is really up to you,

 

[pickles]

Oh I plan to push the limit I'll at a minimum use 6 ga. Thanks for the input all.

 

[BrewBeemer]

Depending on the cords length you also must consider derating the ampacity
of the cord used or go up in size (lower AWG number) call VD.