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Unread 06-03-2014, 16:20
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Ether Ether is offline
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Re: Be aware of battery and charger inconsistencies!

Quote:
Originally Posted by Ether View Post
...you could multiply the RCM by (25/60) to get an Ahr rating (at 25 amps down to 10.5V)...
Note:

The Ahr rating will increase if measured with a lower current.

So be careful when comparing FRC Ahr to automotive Ahr computed from RCM*(25/60).

I eyeballed some data from the discharge curves in NP-18-12 datasheet and plotted the actual Ahr of that FRC-legal battery vs discharge current.

At the RCM 25 amp rate, the FRC battery appears to be less than 7Ahr, which would correspond to an RCM of about 17 minutes.


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