Outer Limits 4x4 Board

After being stranded 70km out in the bush with a flat battery recently, a friend has given me a huge "Trojan SCS225 deep cycle marine battery" he has had just sitting around on a charger. With the intention of throwing it in the back when we do future trips, just in case.

This thing is 820 "marine cranking amps" It's 130 amp hour,
and says it has a "run time of 7.1 hours at 15 amps"

Apart from the fact that you almost need an engine hoist to move the blasted thing, it has raised a few questions.
* What is the difference between marine cranking amps, and cold cranking amps?
* Is this suitable for starting a turbo diesel if the main battery should go flat.
* My charger has the option of 2amps through to 15amps for recharging. Planning on keeping it on the charger to have it ready when we go away, which setting would I use for the charging rate.
* Once I do go down the road of putting in a dual battery system, this may become the camp lighting battery provided it would be suited to slow drain 12volt lighting around the camp. Will this battery suit this sort of use, and does the "7.1 hours run time at 15amp" mean it will run a 15 amp light for 7.1 hours? or what does that rating actually mean.

Thanks in advance.
I did look to see if there was a "sticky" note explaining battery types etc. But didn't find one.

Trent

*Only difference is the temperature at which the crank amps is measured IIRC CCA is at 0 degrees C, MCA is at 15 degrees C. Actual load test is the same.

*Should be suitable as a second line battery. Marine cycle batteries are halfway between cranking batteries and deep cycle batteries in their construction, so have the benefits/disadvantages of both.

*Charging rate should be self regulating, real requirement is for the correct voltage, You should be able to leave the charger on 15 amp setting (my guess this is the current limiting function ie maximum current, rather than an actual constant current source). It should float itself at about 50 mA after a day or so. If you are really concerned after it hasd charged at 15 amps for a day or two you can reduce the charger to its 2 amp setting.

*Battery is ideally suited to this sort of use (similar to running radios on a boat with the engine not running). It will run 15 amps of whaever for 7.1 hours, or 30 amps for about 3-3.5 hrs, or 7.5 amps for about 15 hrs. It will run your fridge (2.5 amp.hours) for about two days. Use LED lights around the campsite and an 80 watt solar panel, and you may only need to start you vehicle to charge the battery fully every 3-4 days or so. Two 80 watt solar panels and you may not need to start your vehicle at all.

I have an Exide ST620 as my start battery...starts the bastard real quick, also runs my winch a lot better than my ED5 deep cycle . when my ED5 dies, i'll be replacing it with another ST620 and join the 2 for winching...well maybe.

http://www.exide.com.au/products/marine.php

your marine battery should be fine

cheers

OONDY