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Current carrying capacity of wire by gauge size

Started by AK July 10, 2019
Having a hard time finding something that isn't rocket science.

I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-)

I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet.

I found this.

https://www.engineeringtoolbox.com/wire-gauges-d_419.html

Any recommendations?

On Wed, 10 Jul 2019 19:55:09 -0700 (PDT), AK
<scientist77017@gmail.com> wrote:

>Having a hard time finding something that isn't rocket science. > >I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) > >I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. > >I found this. > >https://www.engineeringtoolbox.com/wire-gauges-d_419.html > >Any recommendations?
Shielding shouldn't matter a great deal, the shield isn't there to carry current. In industrial applications the shield is only connected (to ground) at one end. Computers and peripherals do connect at both ends. Ampacity of the wire gauge has as much to do with the application and environment as anything... That table is a good one. You'd need to de rate (use a larger gauge) if it were in a hot environment, well insulated, etc.. It is all about heat due to resistance and voltage loss due to resistance. Different insulations stand heat better than others. Another consideration is how much voltage drop are you willing to put up with? Wire has resistance and a long run can adversely affect the voltage available at the load end. As copper heats, resistance goes up, another consideration... And if you buy your wire on Ebay see if it is actually copper and not CCA Copper Covered Aluminum - you wouldn't use a copper wire table for aluminum wire.
On Wed, 10 Jul 2019 19:55:09 -0700 (PDT), AK
<scientist77017@gmail.com> wrote:

>Having a hard time finding something that isn't rocket science. > >I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) > >I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. > >I found this. > >https://www.engineeringtoolbox.com/wire-gauges-d_419.html > >Any recommendations?
https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html They give a table to select wire size no rocket science involved, (this is a recommendation for 12V and a <3% drop in voltage) 15 feet use 16 AWG 20-25 feet use 14 AWG Etc.
On Thursday, July 11, 2019 at 4:03:56 AM UTC-5, default wrote:
> On Wed, 10 Jul 2019 19:55:09 -0700 (PDT), AK > <scientist77017@gmail.com> wrote: > > >Having a hard time finding something that isn't rocket science. > > > >I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) > > > >I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. > > > >I found this. > > > >https://www.engineeringtoolbox.com/wire-gauges-d_419.html > > > >Any recommendations? > > Shielding shouldn't matter a great deal, the shield isn't there to > carry current. In industrial applications the shield is only > connected (to ground) at one end. Computers and peripherals do > connect at both ends. > > Ampacity of the wire gauge has as much to do with the application and > environment as anything... That table is a good one. You'd need to > de rate (use a larger gauge) if it were in a hot environment, well > insulated, etc.. It is all about heat due to resistance and voltage > loss due to resistance. Different insulations stand heat better than > others. > > Another consideration is how much voltage drop are you willing to put > up with? Wire has resistance and a long run can adversely affect the > voltage available at the load end. As copper heats, resistance goes > up, another consideration... > > And if you buy your wire on Ebay see if it is actually copper and not > CCA Copper Covered Aluminum - you wouldn't use a copper wire table for > aluminum wire.
Thanks for the good info. Andy
On Thursday, July 11, 2019 at 7:15:04 AM UTC-5, default wrote:
> On Wed, 10 Jul 2019 19:55:09 -0700 (PDT), AK > <scientist77017@gmail.com> wrote: > > >Having a hard time finding something that isn't rocket science. > > > >I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) > > > >I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. > > > >I found this. > > > >https://www.engineeringtoolbox.com/wire-gauges-d_419.html > > > >Any recommendations? > https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html > > They give a table to select wire size no rocket science involved, > (this is a recommendation for 12V and a <3% drop in voltage) > > 15 feet use 16 AWG > 20-25 feet use 14 AWG > > Etc.
I will be using 120 Volt AC. Current draw may be up to 15 amps. Andy
Voltage is not important, since insulation is good (plastic envelope).
Consider 1mm^^2=10A max (not permanent).
For 15A, I would suggest at least 2mm^^2, 1.5mm^^2 would be a little too 
thin !
Mono or multi wire, it is not important ; this only apply at higher 
frequency.

AK a &eacute;crit le 11/07/2019 &agrave; 15:50&nbsp;:
> On Thursday, July 11, 2019 at 7:15:04 AM UTC-5, default wrote: >> On Wed, 10 Jul 2019 19:55:09 -0700 (PDT), AK >> <scientist77017@gmail.com> wrote: >> >>> Having a hard time finding something that isn't rocket science. >>> >>> I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) >>> >>> I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. >>> >>> I found this. >>> >>> https://www.engineeringtoolbox.com/wire-gauges-d_419.html >>> >>> Any recommendations? >> https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html >> >> They give a table to select wire size no rocket science involved, >> (this is a recommendation for 12V and a <3% drop in voltage) >> >> 15 feet use 16 AWG >> 20-25 feet use 14 AWG >> >> Etc. > I will be using 120 Volt AC. > > Current draw may be up to 15 amps. > > Andy
On Thu, 11 Jul 2019 06:50:57 -0700 (PDT), AK
<scientist77017@gmail.com> wrote:

>On Thursday, July 11, 2019 at 7:15:04 AM UTC-5, default wrote: >> On Wed, 10 Jul 2019 19:55:09 -0700 (PDT), AK >> <scientist77017@gmail.com> wrote: >> >> >Having a hard time finding something that isn't rocket science. >> > >> >I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) >> > >> >I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. >> > >> >I found this. >> > >> >https://www.engineeringtoolbox.com/wire-gauges-d_419.html >> > >> >Any recommendations? >> https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html >> >> They give a table to select wire size no rocket science involved, >> (this is a recommendation for 12V and a <3% drop in voltage) >> >> 15 feet use 16 AWG >> 20-25 feet use 14 AWG >> >> Etc. > >I will be using 120 Volt AC. > >Current draw may be up to 15 amps. > >Andy
That's easy enough then... you need a minimum of 14 AWG if the circuit breaker says 15 and 12 if it is 20. If it is going between wall spaces (concealed wiring) then there is a local electrical code that comes into play for the type of insulation and whether it needs to be armored cable, run in conduit, etc..
Shield is only there for shielding.
It has no participation in the current distributed.

default a &eacute;crit le 11/07/2019 &agrave; 20:32&nbsp;:
> On Thu, 11 Jul 2019 06:50:57 -0700 (PDT), AK > <scientist77017@gmail.com> wrote: > >> On Thursday, July 11, 2019 at 7:15:04 AM UTC-5, default wrote: >>> On Wed, 10 Jul 2019 19:55:09 -0700 (PDT), AK >>> <scientist77017@gmail.com> wrote: >>> >>>> Having a hard time finding something that isn't rocket science. >>>> >>>> I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) >>>> >>>> I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. >>>> >>>> I found this. >>>> >>>> https://www.engineeringtoolbox.com/wire-gauges-d_419.html >>>> >>>> Any recommendations? >>> https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html >>> >>> They give a table to select wire size no rocket science involved, >>> (this is a recommendation for 12V and a <3% drop in voltage) >>> >>> 15 feet use 16 AWG >>> 20-25 feet use 14 AWG >>> >>> Etc. >> I will be using 120 Volt AC. >> >> Current draw may be up to 15 amps. >> >> Andy > That's easy enough then... you need a minimum of 14 AWG if the > circuit breaker says 15 and 12 if it is 20. If it is going between > wall spaces (concealed wiring) then there is a local electrical code > that comes into play for the type of insulation and whether it needs > to be armored cable, run in conduit, etc..
In article <c8f3ea47-476c-418e-ab31-bff61565dea7@googlegroups.com>, 
scientist77017@gmail.com says...
> > I will be using 120 Volt AC. > > Current draw may be up to 15 amps. > > Andy > >
As others are going to say, use # 14 wire minimum. Remember that you are really dealing with 50 feet instead of 25 feet if your load is 25 feet from the source.
On 7/10/2019 9:55 PM, AK wrote:
> Having a hard time finding something that isn't rocket science. > > I thought that since it takes shielded wires to get the current necessary to run electronic items, it would loosely be related. :-) > > I want to know the current carrying capacity of shielded wire by the wire gauge for runs of less than 25 feet. > > I found this. > > https://www.engineeringtoolbox.com/wire-gauges-d_419.html > > Any recommendations? >
There are different criteria that need to be considered. In no particular order. 1) How much voltage drop can your circuit handle without malfunction. Using numbers from the link you posted, Let's assume you have a #22 wire, it has 52 ohms per 1000ft, or 5.2 ohms per 100 ft. If you have a circuit that requires 12 volts and draws 1 amp, and you have a 50 ft run (50ft each way equals 100 ft total) of #22 wire. To find the voltage drop caused by the wire you multiply. 1 amp x 5.2 ohms equals a voltage drop of 5.2 volts. That means you would need a supply of 12volts + 5.2 volts = 17.2 volt supply to make sure you have 12v at your circuit. And then someone recommended #14 wire for 15 amps, that is in the electrical code, you must limit current to 15 amps with a fuse or circuit breaker for a #14 wire. Code says if you use #12 wire you must limit current to 20 amps. Please make me explain any of that again if you don't understand. 2) Heat build up in the wire from the current flow. If you have too much current flowing in the wire it will get HOT. How much heat can the insulation handle before melting or before starting a fire. 3) Fusing of the wire, at some high current the wire will actually melt like a fuse. To operate, a circuit must be complete, meaning start at the power supply, a wire to the circuit, through the circuit, a wire back to the power supply. So two wires. A shield is something different, but the shield can be one of the wires just discussed. Look up coax. Or it may be a separate wire that is usually grounded. Look up shielded pair. Can you rephrase your question with any new information you have learned. Maybe with volts, amps, or? Mikek