<< 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.
----- Original Message -----
From: "David Joyce" <davidjoyce@doctors.org.uk>
Subject: Europa-List: Re: Your 914 Rectifier problem
> <davidjoyce@doctors.org.uk>
>
> Mark, That is very helpful. What you describe with your voltmeter fits in
> exactly with my ammeter findings. I will replace the regulator and expect
> to
> cure the problem. In our situation we could measure the drain on the
> battery, and having turned off everything except the radio and the fuel
> pump
> this amounted to 3 amps with a topped up 16 amp/hours battery I reckoned
> this gave us 5 hrs flying probably and certainly at least enough time to
> complete a 20 min sea crossing. I am copying this to the list as I suspect
> we won't be the last to have such a problem.
> Regards, David
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