<<Does the 80% figure apply to pure
> lead/gas recombinant batteries, >>
Yes, its a function of the chemistry rather than the physics of
construction. However,, the better type of battery would take longer to
degrade to 80% capacity, excepting that the 'regulations' (i.e. JAR design
codes) only allow 80% for the purpose of calculation.
Glad you made it across the Channel; I would have made the same decision!
Rgds.,
Duncan.
----- Original Message -----
From: "David Joyce" <davidjoyce@doctors.org.uk>
Subject: Re: Europa-List: Re: Your 914 Rectifier problem
> <davidjoyce@doctors.org.uk>
>
> Duncan, Thanks for that. I wasn't planning of course to push my luck for
> anything like 5 hrs. It was simply my starting position for working out
> whether I could expect it to get across the shortish Dunkerque-Dover
> crossing with pump and radio working. Does the 80% figure apply to pure
> lead/gas recombinant batteries, which claim all sorts of qualities not
> possessed by ordinary lead/acid batteries?
> Regards, David----- Original Message -----
>
>
> <ami@mcfadyean.freeserve.co.uk>
>>
>> << 3 amps with a topped up 16 amp/hours battery I reckoned
>> > this gave us 5 hrs flying >>
>>
>> David,
>> This is a rather an optimistic calculation because:
>> 1.Battery capacity is quoted at the 20 amp.hour rate. When discharged at
>> higher rates there is progressively less capacity.
>> 2.A brand new battery may have the full amp-hour capacity, but it is
> normal
>> to allow only 80% of this for a battery in good condition. "State of
> charge"
>> or terminal voltage is no indication of battery capacity.
>>
>> If you want to be sure about the state of a battery at any one time then
>> you'd need an integrating ammeter, which keeps an account of amps-in an
>> amps-out, with presettable factors to allow for self discharge etc.
>>
>> Regards,
>> Duncan.
>
>
>
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