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UK Camping (uk.rec.camping) 

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Where to get a leisure battery?
Hi all,
I'm interested in running a 12v coolbox from a leisure battery this w/end. The ones I've seen just seem to have terminals. Do they exist with cigarette lighter sockets? Anywhere online that sells them or something similar? cheers Steve 


Where to get a leisure battery?
"Steve Davis" wrote in message ... Hi all, I'm interested in running a 12v coolbox from a leisure battery this w/end. The ones I've seen just seem to have terminals. Do they exist with cigarette lighter sockets? Anywhere online that sells them or something similar? cheers Steve You can buy an adapter, crocodile clips at one end and a cigarette lighter socket at the other. 


Where to get a leisure battery?
Try your local camping shop  there is an adapter that has clips to
cigarette lighter. "Steve Davis" wrote in message ... Hi all, I'm interested in running a 12v coolbox from a leisure battery this w/end. The ones I've seen just seem to have terminals. Do they exist with cigarette lighter sockets? Anywhere online that sells them or something similar? cheers Steve 


Where to get a leisure battery?
"highgateuk" wrote in message ... "Steve Davis" wrote in message ... Hi all, I'm interested in running a 12v coolbox from a leisure battery this w/end. The ones I've seen just seem to have terminals. Do they exist with cigarette lighter sockets? Anywhere online that sells them or something similar? cheers Steve Netto are selling cool boxes this week. according to the advert they plug into the cigarette lighter. Price £24.99 ive jus bin an got one. it cools or heats. 24 litre capacity. not a bad lil thing really 


Where to get a leisure battery?
"John Moorhouse" writes:
In , Steve Davis typed: Hi all, I'm interested in running a 12v coolbox from a leisure battery this w/end. The ones I've seen just seem to have terminals. Do they exist with cigarette lighter sockets? Anywhere online that sells them or something similar? cheers Steve Watch the rating of the coolbox, to see if it will flatten the battery, say 5pm friday  5pm sunday = 48 hours, if you get a 110 Amp hour one this will give you just over2 amp current for the 48 hours, check that this will be enough for the coolbox, ours (admittedly a large one) pulls 6 amps, so I can only hope for about 15 / 17 hours running just on the battery, ok for a day out but not for staying overnight. Amp hours rating of the battery / current drawn by cool box = hours you can use it for. To a first approximation that's true but batteries have different capacities for different discharge rates. A 110Ah battery may last quite a bit more than 55 hours for a 2A discharge rate but a 7Ah battery will last a lot less than 3.5 hours with the same load. Chris  Chris Eilbeck MARS Flight Crew http://www.mars.org.uk/ UKRA #1108 Level 2 UYB TRA #9527 PSMR 


Where to get a leisure battery?
Most Battery companies quote their Amp/Hour rating at a 20 hour rate,
"The ampere_hour capacity measures the total amount of electricity stored in a battery. An amperehour represents the ammount of electricity when a current of 1 ampere passes for 1 hour. The amperehour capacity varies with the rate at which the battery is discharged, the slower the discharge the greater the ammount of electricity that a battery will deliver The ampere hour capacity is the ammount of electricity that a battery will deliver during 20 hrs before the voltage falls to 10.5 volts. For example a 60ampere hour battery will delivere a current of 3 amps for 20 hours. We can supply all leisure batteries. www.phoenixauto.co.uk "John Moorhouse" wrote in message ... To a first approximation that's true but batteries have different capacities for different discharge rates. A 110Ah battery may last quite a bit more than 55 hours for a 2A discharge rate but a 7Ah battery will last a lot less than 3.5 hours with the same load. Now I am realy confused !!! Should the specification of a battery therefore include a statement such as : 110Ah at 2 A discarge rate 100Ah at 5 A discharge rate 80 Ah at 10 A discharge rate as it seems from this that the amp Hour capacity is infact meaningless. Ta John 


Where to get a leisure battery?
On Tue, 12 Aug 2003 16:00:17 +0100, "John Moorhouse"
wrote: In , John Cutler typed: John, my comments were more aimed at the previous comment by Chris Elbeck: To a first approximation that's true but batteries have different capacities for different discharge rates. A 110Ah battery may last quite a bit more than 55 hours for a 2A discharge rate but a 7Ah battery will last a lot less than 3.5 hours with the same load. I have always understood the Amp Hour concept that you outlined, although I didn't know about the 20 hour rule, what my confusion was over is this statement and wondered how much the capacity was effected by the discharge rate as indicated above, I see that the greater the current drawn the warmer the battery would get but would it appreciably affect the useable capacity of the battery, ie. would I actually get say 65 hours @ 2 amps, 20 hours @ 5.5 amps and only 8 hours at 11 amps as Chris has suggested out of my 110 amp hour battery ? Along those lines, yes, although the precise figures are almost certainly different. There's a useful concept, "internal resistance"  it's explained fairly well he http://farside.ph.utexas.edu/~rfitzp...es/node43.html http://farside.ph.utexas.edu/~rfitzp...es/node48.html Basically, the more current you draw from a battery, the more stored power is wasted heating up the battery and the less is usefully transferreed to your appliance.  QrizB I sound like I know what I'm talking about, but don't be fooled. 


Where to get a leisure battery?
"John Moorhouse" writes:
In , John Cutler typed: Most Battery companies quote their Amp/Hour rating at a 20 hour rate, "The ampere_hour capacity measures the total amount of electricity stored in a battery. An amperehour represents the ammount of electricity when a current of 1 ampere passes for 1 hour. The amperehour capacity varies with the rate at which the battery is discharged, the slower the discharge the greater the ammount of electricity that a battery will deliver The ampere hour capacity is the ammount of electricity that a battery will deliver during 20 hrs before the voltage falls to 10.5 volts. For example a 60ampere hour battery will delivere a current of 3 amps for 20 hours. John, my comments were more aimed at the previous comment by Chris Elbeck: To a first approximation that's true but batteries have different capacities for different discharge rates. A 110Ah battery may last quite a bit more than 55 hours for a 2A discharge rate but a 7Ah battery will last a lot less than 3.5 hours with the same load. I have always understood the Amp Hour concept that you outlined, although I didn't know about the 20 hour rule, what my confusion was over is this statement and wondered how much the capacity was effected by the discharge rate as indicated above, I see that the greater the current drawn the warmer the battery would get but would it appreciably affect the useable capacity of the battery, ie. would I actually get say 65 hours @ 2 amps, 20 hours @ 5.5 amps and only 8 hours at 11 amps as Chris has suggested out of my 110 amp hour battery ? That sounds entirely reasonable to me. Check the spec sheet of the battery you intend to use on the manufacturer's website. They'll normally give discharge curves for different loadings. Chris  Chris Eilbeck MARS Flight Crew http://www.mars.org.uk/ UKRA #1108 Level 2 UYB TRA #9527 PSMR 