correct wiring for boat

[Guest]

Hi guys and girls

I have a question...... i need to know the correct gauge of wire for the positive and negative feeds/returns to my switch unit, i know it has to come from the battery through an isolator into the switch unit/fuse box but have no idea of the gauge.

any hep or links will be very appreciated.

thankyou

Ian

[Antares_9]

Here you go, first work out how many amps draw maximum the cable will be subjected to then use the table below. The sizes are AWG (American wire gauge) but I'm sure google will find you a conversion table for mm squared. Also remember the length is "round trip" for both the feed and return not just the distance to the load.

Distance - Feet

10 15 20 25 30 40 50

Amps Wire Gauge

5 18 16 14 12 12 10 10

10 14 12 10 10 10 8 6

15 12 10 10 8 8 6 6

20 10 10 8 6 6 6 4

25 10 8 6 6 6 4 4

30 10 8 6 6 4 4 2

40 8 6 6 4 4 2 2

50 6 6 4 4 2 2 1

60 6 4 4 2 2 1 0

70 6 4 2 2 1 0 2/0

80 6 4 2 2 1 0 3/0

90 4 2 2 1 0 2/0 3/0

100 4 2 2 1 0 2/0 3/0

120 4 2 1 0 2/0 3/0 4/0

140 2 2 0 2/0 2/0 4/0 4/0

160 2 1 0 2/0 3/0 4/0 4/0+4

180 2 1 2/0 3/0 3/0 4/0+10 4/0+2

200 2 0 2/0 3/0 4/0 4/0+4 4/0+0

[Guest]

Thanks anteras 9 that great

Ian

[goodall_m1]

Here you go, first work out how many amps draw maximum the cable will be subjected to then use the table below. The sizes are AWG (American wire gauge) but I'm sure google will find you a conversion table for mm squared. Also remember the length is "round trip" for both the feed and return not just the distance to the load.

Distance - Feet

10 15 20 25 30 40 50

Amps Wire Gauge

5 18 16 14 12 12 10 10

Ian:

Pity the forum software lets you type in a monospaced font (so every thing lines up)

and then displays it in a proportional font (characters different widths)

so that they don't line up anymore!

Hint:

Use highlight and ctrl/c (copy) to extract the table, paste it in a notepad window and change the font to Courier

to you will get the table displayed properly!

Martin

[goodall_m1]

Pity the forum software lets you type in a monospaced font (so every thing lines up)

and then displays it in a proportional font (characters different widths)

so that they don't line up anymore! Martin

Oops should have tried it first!

Shows up in line in the entry screen but not when moved to Notepad,

the table must have TAB characters in it me thinks...

[goodall_m1]

Ok so lets try a screen shot...

OH can't paste a screen shot into a post either

Ah but I have a cunning plan, lets take a shot of the screen..

Simples!

(I will take any excuse to fiddle with my new camera)

[mjt]

OH can't paste a screen shot into a post either

If you can paste a photo JPEG into your post why not a screenshot JPEG? Getting screenshots in Windows is a bit more fiddly than in MacOS but you can do it thusly:-

Capture your screenshot (Alt/PrintScreen) then paste into Windows' 'Paint' app. Marquee round the bit of the screenshot you want and 'Cut' or 'Copy'. Open a new window (answering NO to 'Save Untitled?') and paste the copy in. Then use Save As... and save as a JPEG.

[Guest]

hey you clever guys

thanks again, looks like i will be on the water soon

Ian

[newf]

On the wiring theme has anybody any good contacts for heavy duty cable i.e. 65 amp or near. I have tried googling but get very patchy results.

[Guest]

Colin, try John Grandshaw at http://www.jgtech.com He's very well stocked, and very helpful if you call him.

Bruce

[newf]

Bruce, I'll have a look