What amp for Cable

[BorgPS17]

if the fuse needed is 30 amp, would that also mean that the cable has to be rated at the same amps or greater...YES??

Thanks for your reply's.

[nj swb]

if the fuse needed is 30 amp, would that also mean that the cable has to be rated at the same amps or greater...YES??

Thanks for your reply's.

Yes.

The fuse is there to protect the cable (and consequently, anything else that may be damaged if the cable overheats / catches fire).

The cable rating must always be higher than the fuse rating.

To complicate the issue, the cable rating is affected by how it is installed. Cables are generally rated at 25 degrees Celsius, in free air. Under the bonnet of your vehicle, or tucked under the carpet in your Pajero crossing the Simpson in 45 degree heat, the cable won't be able to carry as much current. So it's generally a good idea to generously oversize the cable i.e. consider 40A plus cable rating for a 30A fuse.

Then there's the issue of voltage drop - generally not an issue over a short lengths (think under-bonnet), but can be significant for longer runs (think back of the vehicle).

If in doubt - ask! We're here to help.

[BorgPS17]

Thanks for your reply nj swb

was thinking 50amp cable, going from starter battery to ctek charger at back of vechile, where the aux battery will be sitting.

[Dicko1]

Thanks for your reply nj swb

was thinking 50amp cable, going from starter battery to ctek charger at back of vechile, where the aux battery will be sitting.

Get 6 b&s..Be careful buying from an autoelectrician as many will supply 6mm which is too small.

[BorgPS17]

Get 6 b&s..Be careful buying from an autoelectrician as many will supply 6mm which is too small.

6 b&s.... ?

please explain.

would this do.?

http://www.ebay.com.au/itm/10-Metre-6-B-S-Twin-Core-Automotive-Auto-Cable-2-GRY-Anderson-Style-DC-Plugs-/112597750861?_trksid=p2385738.m2548.l4275

[Turorit]

6 b&s.... ?

please explain.

would this do.?

http://www.ebay.com.au/itm/10-Metre-...38.m2548.l4275

Thats the one

Here's an explanation of the various wire sizing

https://www.redarc.com.au/images/uploads/files/wire_gauge_worksheet.pdf

[zoiks]

With cables you have to watch for 2 things. Temperature and voltage drop.
For your situation a 6AWG/B&S cable should be sufficient.

[Sparky3975]

The primary purpose of fuse for the protection of the cabling. As has already been stated, there are various conditions that effect cables (temp, construction, insulation characteristics, installation methods, length). As a general rule of thumb I use is to find the cable size that will carry the constant current required by the device, etc and then go up a cable size and de-rate the cable using a smaller fuse. Going up a cable size will help reduce temperature and voltage drop issues but you may also encounter termination issues when it comes to connections (this can lead to other issues).

Good luck with your wiring.

[BorgPS17]

have cable ordered.
have 2 circuit breakers ordered.

next thing is do i put the battery in a box with all the fitting connected.
or do i just make a place to put the battery in and connect every thing to the battery.?

Any suggestions....

Rdgs.

Thank for all you posts.

[whynot]

Buy a battery box and add your plugs and volt meter. Make sure all are fused and use an Anderson plug to connect your supply to your battery. Makes it easy for a quick disconnect.

Worth investing in a hydraulic crimper for the heavy leads/ plugs. I picked up a Matson crimper from ebay for $100 and it does the job well.
If you are running a fridge straight from the battery change that plug to an anderson as well.

[BorgPS17]

Buy a battery box and add your plugs and volt meter. Make sure all are fused and use an Anderson plug to connect your supply to your battery. Makes it easy for a quick disconnect.

Worth investing in a hydraulic crimper for the heavy leads/ plugs. I picked up a Matson crimper from ebay for $100 and it does the job well.
If you are running a fridge straight from the battery change that plug to an anderson as well.

Thanks for the TIP about the Crimper....Ordered from ebay $83

[Trisome]

After you have installed everything, check for volt drop. use a multimeter turn on everything you are going to use down line, and check the voltage at the battery, and then at the fridge or whatever you are using.

Trisome