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[Deleted] Misleading wire size chart

300A with 4ga wire? That chart needs to be destroyed before someone burns down their house.
 
Thank you for posting, and for contributing resources to the community. BUT--and its a big BUT--This is not an ampacity chart, and some of these currents (on the far left) would not be safe for the wire gauges indicated. This table appears to be in reference to voltage drop, not ampacity.

A couple quick ways to tell:
1. If it doesn't list wire insulation temperature, and probably other variables, its almost certainly not taking ampacity/safe current carrying capacity into consideration
2. If it does list distances its almost certainly a voltage drop chart.

As a reference point, here is the baselines Ampacity chart from the NEC (for single conductors at or below 30*C/85*F):
full
 
Thank you for posting, and for contributing resources to the community. BUT--and its a big BUT--This is not an ampacity chart, and some of these currents (on the far left) would not be safe for the wire gauges indicated. This table appears to be in reference to voltage drop, not ampacity.

A couple quick ways to tell:
1. If it doesn't list wire insulation temperature, and probably other variables, its almost certainly not taking ampacity/safe current carrying capacity into consideration
2. If it does list distances its almost certainly a voltage drop chart.

As a reference point, here is the baselines Ampacity chart from the NEC (for single conductors at or below 30*C/85*F):
full
OMG, I am so sorry, I thought it looked great, thanks for the correction. I'll take it down right away
 
OMG, I am so sorry, I thought it looked great, thanks for the correction. I'll take it down right away
No worries, it can be really confusing at first, particularly since many charts and calculators do a really poor/irresponsible job at indicating whether they are just voltage drop, ampacity, or both. You are definitely not the first to confuse the two, its one of the most common points of confusion here, and it confused me for a long time as well (i'm still working out the finer points)
 
I stopped using charts. I switched to the calculators because I want to know the results for my specific length of wire/cable.

FWIW, Bay Marine Supply has their voltage drop calculator back up:

 
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