Re: koolatron 12v cooler drain my battery

"lbbs" <[EMAIL PROTECTED]> wrote:

>
>"Anthony Matonak" <[EMAIL PROTECTED]> wrote in message
>news:[EMAIL PROTECTED]
>> lbbs wrote:
>> > I saw koolatron 12v cooler for the road.   Just wondering how many hours can
>> > you run on the battery before it could be damaging effect on the battery.
>>
>> I did a quick websearch and it seems it uses 3 amps (36 watts).
>> A typical car battery ranges from 50 to 100 amp-hours of storage.
>> Most of these batteries can be damaged by draining them more than
>> 80%. For a small battery this would be 40 amp-hours or about
>> 13 hours.

No no no!!!  Car batteries will have their lives seriously shortened when
drained this much.  Also, as you get into the cheaper car batteries the service
life is squat even without extra loads.  Car batteries are designed for high
initial cranking power and relatively little reserve power.  Discharge more
than 40% at your own risk.

>So is that 13 hours while the engine is running or when it is off?   Could
>you turn it on for a couple of hours during the day when engine is off
>(safely).   And then how many hours would you have to drive before the
>battery would be fully charged again?

Arrgh.  Charging rates are too complicated to go into detail here.  Do a google
search or ask an RVer.  The fast charge to bring a battery up to power is only
a surface charge and is not a complete charge.  Proper charging requires a
trickle charge over a long period of time.  Look up "equalization charge" for
more info.  Extended use of something like this is asking for trouble.  Keep an
emergency starter battery in the car if you plan to use it this way.

>>This is only for a brand new battery. An old battery will have less capacity.

>> You should note that these things only go a maximum of 40 deg
>> below ambient temperature. This means if it's 110 outside that
>> the cooler will only be 70 deg. The inside of a car, especially
>> one parked in the sun, can often be over 150 degrees.
>>
>> Anthony
>>
>

>From the Koolatron FAQ:
How long can a Koolatron be left in a car before there is a risk that the
battery level will be too low to start the engine? 

The definition of a battery can range between:
A. A large new, battery, heavy duty model for a full sized North American car. 
B. A small, old, light duty model for a compact or sub-compact car which may be
in poor condition. 
For battery A, on a hot day, a Koolatron running for 4-6 hours will likely not
affect the capability to start the engine. With battery B, two hours would
likely be the maximum time allowed. 

Homemade peltier chest:
<http://216.239.57.104/search?q=cache:zd7akxgrxLgJ:www.cheek.org/tech/015.htm+ice+chest+peltier&hl=en&ie=UTF-8>

Words from the wise.
http://4xforum.co.za/market/freezers.html
(In short, the peltier chests are toys.  Compressor chests work.)

Engel fridges:
http://www.piranhaoffroad.com.au/products/fridges/engel/EngelRange.htm 

http://store.yahoo.com/cruiserconnection/enfreezfrid.html

One on eBay for less:
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