Maker Pro
Maker Pro

Looking for a 12 v dc "PowerPack" battery that produces A/C

W

W. eWatson

Jan 1, 1970
0
W. eWatson wrote:

(...)


Practically speaking, that is probably close enough,
considering the negative effects of complete discharge.

As you mentioned, discharging the battery 70% in 5 hours
leads one to believe that we are looking at 14% discharge
per hour, or a total run time of about 7.1 hours before
the battery is totally flat.

(70% discharge / 5 hours = 14% hourly discharge rate)
and 1 / 14% = 7.14 hours total run time)

Your CPAP unit appears to be drawing about 3.36 A because:
24 AH / 7.14 hours = 3.36 A or about 41 W

Looked at another way, 3.36 A * 7.14 H = 24 AH

That is not *quite* as high as 5 A. :)

--Winston
Be aware that my memory may not be accurate on that matter. I did the
experiment about 6 weeks ago.
 
W

Winston

Jan 1, 1970
0
W. eWatson said:
On 2/24/2012 2:48 PM, Winston wrote:
(...)

Be aware that my memory may not be accurate on that matter. I did the experiment about 6 weeks ago.

Your ammeter measurement will show the real info.

If your battery is new, it could be more than 24 AH.
And if it has some hours on it, it could be less than
24 AH of capacity. This would affect my guess pessimistically/
optimistically, respectively. :)

--Winston
 
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