8 replies to this topic

[SolarB]

I need to replace the positive battery cable. Does anyone know the size of a Mini battery cable, or the approximate cranking current for a typical 1275 with an inertia starter motor?

[mini13]

http://www.merlinmot...oduct_info.html

[Dan]

I tend to allow 300 amps, the starter doesn't draw nearly that but the cable is far longer than it would be in most cars. As a result, if you use a cable that is rated close to the starter load then on days when the load is high you will get more excessive volt drop than you should do.

[mikey72]

http://www.thewelder...ing_Cable_.html

worth using a local shop if you can, some are rubber, some are pvc coated.

Edited by mikey72, 30 November 2010 - 12:11 AM.

[lrostoke]

Another source

http://www.vehicle-w...atterycable.php

[L400RAS]

Why not buy an original? At 134" = 3.5m approx, £30 for an original is cheaper than merlin motorsport, and has the ends on already:

127" version
134" version

[SolarB]

Thanks for all the links guys. I don't have a battery cable at the moment and I'm putting in an order to PoleVolt for a lot of bits 'n bobs. They can supply 110, 170, 240 and 345 amp battery cable so it makes sense to order from them at the same time.

I have a few meters of 11.5 mm od cable but it's too big to fit into the cable tray under the car which would appear to take a maximum of 10mm diameter. The 11.5mm that I have is probably around 240A, though I haven't actually sat down and counted all the strands yet.

L400RAS, I'm routing the cable differently from the normal installation and I don't want to buy a ready made cable that probably won't fit.

Dan, your 300A cable must be around 13mm. How do you secure it under the car?

A 10mm diameter cable that would fit the cable tray would be around 170A. Does anyone know the current drawn when starting, or the CSA of the original cable?

[MRA]

There are other types of multi strand cable I can think of one in particular that has 4000 strands but is only rated at 300 Amps.......... this means that it's diameter is smaller

[Wil_h]

I've measured the peak current before and typicaly got 120Amps, but this was on a normal day, 15 degrees. On a cold day I'd expect more than this, maybe 300 Amps, but most likely a little less on our small engines; I'd expect 300amps on a 3 litre motor maybe.

However, 300Amps will be a constant rating, not a short duration rating. Yes it will get hot, but you will never be cranking 300 amps through a 12 Amp rated cable for a sustained period to cause damage.

Fit the biggest you can get in the tray, that's what I'd do.