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Fusing Main Battery Feed
John Bonnett - 29/6/11 at 11:40 AM

it has always worried me that you can fuse every single circuit but if the main battery lead shorts out to Earth for whatever reason, there is absolutely no protection.

So I took this device of my old Peugeot 205 which, in Peugeot circles, is called the Shunt. It is very convenient because it works as a fused distribution terminal. The positive battery cable connects directly to it. I have fitted four main feeds and each has a 20Amp fuse. This is a very convenient little box which I thought might be of interest.

John
[img] Shunt
Shunt [/img]

[Edited on 29/6/11 by John Bonnett]

[Edited on 29/6/11 by John Bonnett]

ReMan - 29/6/11 at 11:56 AM

The convenience is useful, but if I understand correctly a "Shunt Fuse" is not a fuse at all, it is a link.
So what you have no different from any other distribution fuses in a different place.

John Bonnett - 29/6/11 at 12:41 PM

quote:
Originally posted by ReMan
The convenience is useful, but if I understand correctly a "Shunt Fuse" is not a fuse at all, it is a link.
So what you have no different from any other distribution fuses in a different place.


That's right, big advantage is that the cable from the battery to the fuses is very short and
it was very convenient already having the battery cable connected and the heavy duty connectors all ready wired.

I'm lazy you see

John

coozer - 29/6/11 at 01:03 PM

Good idea, this one is off the current Nissan Note.

Bolts directly to the battery, has a fused 250a link to the starter and 4 outputs of 60~80a.

John Bonnett - 29/6/11 at 02:47 PM

quote:
Originally posted by coozer
Good idea, this one is off the current Nissan Note.

Bolts directly to the battery, has a fused 250a link to the starter and 4 outputs of 60~80a.



Even better, being right on the battery

John

snowy2 - 29/6/11 at 07:22 PM

Personally i wouldn't bother, millions of cars have driven millions of miles and never needed them.....neither do you. ( a small short on a circuit with a 5A fuse is enough to start a fire, your fuse above would have to be 50+A to be of any worth or use!)
Build the car right and dont worry.

What about foam filled fuel tank? 4/5 point harness? massive roll cage? helmet when driving? ABS? air bag? side impact protection? all of these are more likely to be of use to you, i have been a mechanic for 20+ years and have yet to see a fire caused by a random electrical fault. plenty of minor loom fires from shorts but never a major fire.
quite a few by dodgy fuel lines and bodged carbs but not electrical....a fair few by brake fluid spilling onto a hot manifold, but not shorted battery's..... are you seeing a pattern here?

fastfu - 29/6/11 at 09:48 PM

quote:
Originally posted by coozer
Good idea, this one is off the current Nissan Note.

Bolts directly to the battery, has a fused 250a link to the starter and 4 outputs of 60~80a.



Ive got one of them in my shed off my old 350z that you can have if you want to give it a try

Davegtst - 30/6/11 at 08:48 AM

I have a main fuse but only really because of the electric reverse. Instead of using parts from other cars just get one of these, they are made for the job Maxi fuse holder