# OT: Electrical question

Discussion in 'Computer Support' started by Watcher of the Skies, Jun 25, 2003.

1. ### Watcher of the SkiesGuest

Can anyone give me the formula for calculating the Max AMPAGE a cable can
carry by counting the strands and measuring their diameter with a
micrometer?

THANX

Watcher of the Skies, Jun 25, 2003

Re: Electrical question

X-No-Archive: Yes
Errrrr...erm... Watcher of the Skies said:

> Can anyone give me the formula for calculating the Max AMPAGE a cable can
> carry by counting the strands and measuring their diameter with a
> micrometer?
>
> THANX

I'm sure that someone could, but they might ask if it's copper wire or steel.

3. ### BuffaloGuest

Re: Electrical question

The amt of amperage a wire can carry usually also depends on its insulation
and its length.A short bare wire in free air can carry a lot.
For instance, a #12awg wire with poor temp insulation in a pipe is usually
only good to about 20 amps while a bare #12 awg wire in free air can carry
50amps, more or less. Stranded wire can usually carry more current than a
solid wire of the same awg rating because of its increased surface area.
This link will relate wire diameter to awg.
http://www.hardwarebook.net/table/AWG.html

"Watcher of the Skies" <> wrote in message
news:FwkKa.379\$...
> Can anyone give me the formula for calculating the Max AMPAGE a cable can
> carry by counting the strands and measuring their diameter with a
> micrometer?
>
> THANX
>
>

Buffalo, Jun 25, 2003
4. ### KennyGuest

Re: Electrical question

I did this as part of BTEC but can't remember, have a look here:
http://www.epanorama.net/documents/wiring/wire_resistance.html

--

Kenny

"Watcher of the Skies" <> wrote in message
news:FwkKa.379\$...
> Can anyone give me the formula for calculating the Max AMPAGE a cable can
> carry by counting the strands and measuring their diameter with a
> micrometer?
>
> THANX
>
>

Kenny, Jun 25, 2003
5. ### JohnGuest

Re: Electrical question

Depends whether copper or aluminium, whether armoured, unarmoured, whether
run in air or underground, ambient temp?., how many cables run together.

Determine xsection area of each strand multiply by no. of strands in core to
find sq.mm, then refer to IEE Wiring regulations to obtain current rating
for that size.

J.
"Watcher of the Skies" <> wrote in message
news:FwkKa.379\$...
> Can anyone give me the formula for calculating the Max AMPAGE a cable can
> carry by counting the strands and measuring their diameter with a
> micrometer?
>
> THANX
>
>

John, Jun 25, 2003
6. ### Watcher of the SkiesGuest

Re: Electrical question

Ah - somebody who knows what I am talking about & doesn't take the piss out
of my spelling.
Thanks
Thank to all the rest who tried
Hi Bear Nation gets the "killfile" for his contribution.

"Kenny" <> wrote in message
news:bdcuku\$rq3qu\$...
> I did this as part of BTEC but can't remember, have a look here:
> http://www.epanorama.net/documents/wiring/wire_resistance.html
>
> --
>
> Kenny
>
>
> "Watcher of the Skies" <> wrote in

message
> news:FwkKa.379\$...
> > Can anyone give me the formula for calculating the Max AMPAGE a cable

can
> > carry by counting the strands and measuring their diameter with a
> > micrometer?
> >
> > THANX
> >
> >

>
>

Watcher of the Skies, Jun 26, 2003