Some questions about batteries and jumpstarting

[sgvaibhav]

1) I have a THICK cable, which is used to jumpstart an 8 cylinder 6 liter SUV from a big battery. Can i use this same cable to jumpstart small 4 cylinder cars?

2) How to determine what rating of cable is required for jump-starting my car/battery? What to look for in the battery?

3) I have a 4 cylinder - 1.6L engine petrol car. At the MAX - I can jumpstart from an 8 cylinder - 5.8L Landcruiser. Which of these cables look satisfactory to jumpstart my car?
a)http://uae.souq.com/ae-en/300-amp-car-booster-cable-jumper-cables-4793389/i/
b)http://uae.souq.com/ae-en/car-booster-cable-1200amp-6200267/i/

 

[cchase]

The bigger the cable, the better. To be more specific, the lower gauge the wire, the better.

The size of the engine and battery is irrelevant to jumper cable specifications. You want the heaviest cables you can afford.

 

[eljefino]

Any electrical device will only pull the amperage it needs. If you can't supply it the amps it needs, volts will drop and it will struggle or, in the case of motors, overheat.

WRT jumping batteries, I could get a semi running with cheap 10 ga cables. I'd just have to sit hooked up for a lengthy time to charge its battery from my running car. Fatter cables make it more convenient as one can hook up and go without waiting. However if they are so bulky you remove them from your trunk, they're useless.

 

[Chris142]

The bigger the cables the better. Small cables have more curant and amperage drop.

 

[sgvaibhav]

So a 300 amp cable seems adequate for use on my car (my car sized batteries)

 

[JHZR2]

There are standard ampacity charts for cables of different gauges. This is a transient application, so identifying voltage drop in terms of current x resistance losses, given that a cranking battery will already be down at about 10.5V, you want to make sure you dont take it below 10.2 or 10V.

 

[SHOZ]

4 ga for sure, 6 ga at a minimum. Make sure the clamps are good.

 

[Wolf359]

Wow, talk about amp inflation. Those 300 amp cables look mighty thin, in the US we normally never see cables that thin. They will probably still work, it's just that you will probably have to leave them on for a while so that the live battery ends up charging the dead battery a little, it might not actually be able to draw enough power from a live battery to start a car in cold weather as colder engines typically require more power to turn over. Don't forget to wear safety glasses as exploding batteries from hydrogen gas produced by a dead battery charging and ignited by sparks from the cables aren't that uncommon.

 

[Rand]

those 300 amp cables are not 300 amp.

thats like talking about speakers in peak watts and not RMS.

you want 4gauge wires esp. for normal length 20ft, more is overkill.
6 gauge is min. and will work better if you buy a short set such as 12ft. (vs 20ft cables 6 gauge cables)

http://www.sears.com/capri-tools-heavy-d...mp;blockType=G2

 

[RF Overlord]

Maybe those cables are rated in metric amps...