Running wires

[Miriam C.]

A little search yielded the following max amp/wire gage:
10G:55A
12G:41A
14G:32A
16G:22A
18G:16A

These numbers seem to be from the site below and are for chassis wiring. The chart is great though and has a voltage drop calculator.
http://www.powerstream.com/Wire_Size.htm

[bdosborn]

Miriam,

There have been links to this site before and there's a couple of problems with using the information posted there:

- They don't tell you what kind of insulation is on the wire. Different kinds of insulation have different temperature ratings.
- They don't say if the wire is in free air or in conduit. Wire in conduit holds heat in and can't carry as much current as a wire in free air.
- They don't say what the ambient temperature is. Once again, its all about how much heat the insulation is exposed to.

The chart I posted has a couple of assumptions:

- Typical PVC insulation.
- Wires in conduit (or buried in an insulated wall)
- 30C ambient temperature.

As they say on the site

"As you might guess, the rated ampacities are just a rule of thumb. In careful engineering the voltage drop, insulation temperature limit, thickness, thermal conductivity, and air convection and temperature should all be taken into account."

Here's a great wire wizard that takes all these things into consideration:

http://beta.circuitwizard.bluesea.com/

You could probably get away with using the chart with the higher wire ratings but since most people asking for information here don't have a lot of electrical experience it seems prudent to be conservative and not push the limit.

Bruce

[Miriam C.]

Thanks Bruce. I had that bookmarked one time and lost the whole thing.

You could probably get away with using the chart with the higher wire ratings but since most people asking for information here don't have a lot of electrical experience it seems prudent to be conservative and not push the limit.

Bruce

Bruce that chart, if you read the right column gives a lower by half amp rating than yours. I think yours is probably the more accurate. My point was that the numbers posted came from the wrong column.

The column you would need to use I think is the "maximum amps for power transmition" which seem low.