Battery/Cable/Starter amp level?

[Martin.]

Morning all.

I've been reading into and looking at different battery cables. I've been told that for the length I want (to relocate my battery behind the passenger seat) I need 10.1mm cable (25mm sq core) which is capable of 170 amps.

At the minute I've got an 8mm cable which I'm assuming has a 15mm sq core (capable of 110 amps)

Now my question is, how many amps does the engine/starter motor require from the battery for a start up? How many amps flows through the wires on general running?

The reason I ask is because I was looking at 'Vibe' circuit breakers. I've seen someone use one before when they moved their battery to the boot. Are they necessary? (I don't have any audio equipment to worry about)

Cheers

 

[Martin.]

Anyoneeeeeeeeeeeeeee lol.....................

 

[Fantom]

Can't answer the question but I moved my battery there and used 50mm2 cable and it's way over the top! I'd go for 30mm2 if I were you. I put a 300 amp fuse Near the battery. I think it was 300 anyway. I copied someone on here. The battery has been just as before and I've not noticed any difference at all

 

[Martin.]

Can't answer the question but I moved my battery there and used 50mm2 cable and it's way over the top! I'd go for 30mm2 if I were you. I put a 300 amp fuse Near the battery. I think it was 300 anyway. I copied someone on here. The battery has been just as before and I've not noticed any difference at all

Cheers mate. 50mmsq is a huge cable lol!!!

300 amp fuse seems a lot also... I was looking at 140amp fuse boxes :S maybe that's way too low then.. Hence ideally needing to know how many amps are needed to start the car and how many amps would be classed as a surge lol.

 

[Fantom]

Yeah it is pretty huge! Luckily I managed to squeeze it through the bulkhead where the bonnet release cable goes.

Best bet it just to copy someone who's done what you want to do. Are you using a lightweight battery? I kept the standard one as I don't use the car much, didn't want to have a flat battery all the time

There's quite a bit on here about battery relocation, I had to search through quite a few threads to work out what bits to buy

 

[Martin.]

Yeah it is pretty huge! Luckily I managed to squeeze it through the bulkhead where the bonnet release cable goes.

Best bet it just to copy someone who's done what you want to do. Are you using a lightweight battery? I kept the standard one as I don't use the car much, didn't want to have a flat battery all the time

There's quite a bit on here about battery relocation, I had to search through quite a few threads to work out what bits to buy

Yeah, I've been having a good old read, however can't find anything on the specifics I'm after unfortunately.

I have a light weight battery yeah. I barely use the car, probably 1-2 times a month. Only had a problem with it when the car was untouched for 2.5 months. I do have a cut off switch too though which probably helps.

Just want to know for sure, what size circuit breaker to buy. Don't want to buy one too low and then not be able to even start the car but don't want to go any higher than I need to either.

 

[NorthloopCup]

You want either a 150amp or a 175amp fuse mate. Anything any higher and you run the risk of it not doing it's job believe it or not. Mount the fuse as close to the battery as possible too. I use 30mm2 cable on mine using a red top 25 varley. The battery is located under the passenger seat.
DON'T just pass the cable through a grommet in the bulkhead though if possible. It's just a bodge. Use a longacre through panel connector. Far safer.

 

[Martin.]

You want either a 150amp or a 175amp fuse mate. Anything any higher and you run the risk of it not doing it's job believe it or not. Mount the fuse as close to the battery as possible too. I use 30mm2 cable on mine using a red top 25 varley. The battery is located under the passenger seat.
DON'T just pass the cable through a grommet in the bulkhead though if possible. It's just a bodge. Use a longacre through panel connector. Far safer.

Thanks man. Just what I was after. I've got the same battery as you, I'll definitely go for 25mm2 cable minimum then. Was originally thinking that I could just buy an extra 2 foot of 15mm2 cable and extend mine.

Reckon these fuse box things are actually needed? Happy to fit one for the sake of £10-£15 but if you tell me they're not then I won't bother :rasp:

A 150-170amp box will still allow enough current through to start the car then I take it? As 30mm2 core cable must be capable of 210 amps or something.

I've got a solid plastic screw on the bulkhead, looks almost like a plumbing item. What's the benefit of those longacre items you mention?

Sorry for all the questions

 

[NorthloopCup]

Thanks man. Just what I was after. I've got the same battery as you, I'll definitely go for 25mm2 cable minimum then. Was originally thinking that I could just buy an extra 2 foot of 15mm2 cable and extend mine.

Reckon these fuse box things are actually needed? Happy to fit one for the sake of £10-£15 but if you tell me they're not then I won't bother :rasp:

A 150-170amp box will still allow enough current through to start the car then I take it? As 30mm2 core cable must be capable of 210 amps or something.

I've got a solid plastic screw on the bulkhead, looks almost like a plumbing item. What's the benefit of those longacre items you mention?

Sorry for all the questions

Yeah 25mm2 will be fine. I wouldn't bother extending it, just replace in a larger guage.

I use a mega fuse and fuse holder on mine and they are 100% needed. The original Renault starter/alternator wiring has the fusible link built in to it to protect itself from direct shorts to earth and overloads. It stops a fire from starting if the wiring gets overloaded and too hot. To high an ampage fuse and you'll melt the wiring and set the car on fire before the fuse considers blowing.
I worked out the current draw and stuff for mine but it was ages ago tbh. If you use a fuse holder that's man enough for the job you'll be fine. The most cranking amps are drawn on startup, so if it pops the fuse go to the next size up. You'll be fine with 175 though.

The thicker the cable the more current it flows mate so starting the car is slightly easier. Use the same gauge wire for the earth as well, otherwise it can act as a bit of a 'choke' point.

The longacre through panel connector just allows you to pass the power supply into the car safely. It's plastic encased and your wiring bolts on to it from either side.

 

[Martin.]

Can't find any 170 or 175 amp circuit breakers on eBay arghhh. 140amp seems to be the most common one. But I'm now thinking that this will be too low....

 

[Martin.]

Yeah 25mm2 will be fine. I wouldn't bother extending it, just replace in a larger guage.

I use a mega fuse and fuse holder on mine and they are 100% needed. The original Renault starter/alternator wiring has the fusible link built in to it to protect itself from direct shorts to earth and overloads. It stops a fire from starting if the wiring gets overloaded and too hot. To high an ampage fuse and you'll melt the wiring and set the car on fire before the fuse considers blowing.
I worked out the current draw and stuff for mine but it was ages ago tbh. If you use a fuse holder that's man enough for the job you'll be fine. The most cranking amps are drawn on startup, so if it pops the fuse go to the next size up. You'll be fine with 175 though.

The thicker the cable the more current it flows mate so starting the car is slightly easier. Use the same gauge wire for the earth as well, otherwise it can act as a bit of a 'choke' point.

The longacre through panel connector just allows you to pass the power supply into the car safely. It's plastic encased and your wiring bolts on to it from either side.

Cheers buddy, I'll get on the case then.

This is the item I was looking at originally. Although can't find one for 170amps, seems the next step is 200...

http://www.ebay.co.uk/itm/Vibe-CB14...cles_Terminals_Cabling_ET&hash=item3cb8ef7aab

 

[Martin.]

Found the one which you use..

http://www.ebay.co.uk/itm/Mega-Fuse...arts_Vehicles_CarParts_SM&hash=item338fc838cf

Think I'll go for this and try get some 170amp fuses if they exist.

 

[NorthloopCup]

Found the one which you use..

http://www.ebay.co.uk/itm/Mega-Fuse...arts_Vehicles_CarParts_SM&hash=item338fc838cf

Think I'll go for this and try get some 170amp fuses if they exist.

Yeah that's the one mate. It'll be a 175amp fuse as well.

 

[Martin.]

Yeah that's the one mate. It'll be a 175amp fuse as well.

Nice one. Always helping me out!

 

[colesy]

Sorry to bring up an old thread, today I managed to pop the fuseable link because the starter wiring touched the manifold 😩 from what I’ve read I need 120amp mega fuse? It’s all standard location etc