Jump to content

Another Battery Question


Recommended Posts

I have a question about deciphering what a battery tag says.

Our truck has 4 Deka 904D batteries as house batteries. These are charged by the truck alternator, but not used- isolated- from the truck batteries.

On the label it says-

904D

Cranking- 1280

CCA- 1050

 

What would the usable amperage be for these batteries?

They checked out fine, I desulfated them and brought them up to a full charge- 14.4v

The inverter on the truck is a Statpower Prosine 3000 inverter charger.

Thoughts?

Link to comment
Share on other sites

Google is your friend. :)

 

http://www.wholesalebatteries.net/PDF/Deka%20Marine%20Master%20Specs%20%28June%202009%29.pdf

 

About half way down the page look for the two specs you cited and then follow over to "reserve capacity" which indicates "290". So probably 290 amps for each battery (less any resistance in connectors, cables, etc.).

 

WDR

Link to comment
Share on other sites

Actually.. with a battery like that "reserve capacity" is not measured in amps. It is the reserve capacity in minutes at 80 degrees F to fall below 10.5v @ 25 amps. So you would calculate it at 290rc x .4167 -or- 4.8 hrs @ 25amps = 120ah capacity at the approximate 20 hr rate.

 

120ah x 4 = 480ah @ 50% = 240 "available" ah's.

 

....and... 400lbs. :D

Link to comment
Share on other sites

for those sudo deep cycle, the 50% reserve capacity matches 20 hour amp rating. so these are equivalant 145 amp hour.

 

That's generally a pretty good rule of thumb for a single bank. Across multiple banks of cells it can get you into a little trouble though. In this case about 100ah discrepancy (or 50ah usable)... roughly 20%.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Guest
This topic is now closed to further replies.
×
×
  • Create New...