SailNet Community - View Single Post - Battery Voltages vs Capacity
View Single Post
post #1 of Old 09-20-2004 Thread Starter
Sailboat Reboot
svzephyr44's Avatar
Join Date: Jun 2000
Location: On Board
Posts: 651
Thanks: 4
Thanked 52 Times in 45 Posts
Rep Power: 17
Send a message via Skype™ to svzephyr44
Battery Voltages vs Capacity

I have a classic 1 x 2 battery set up in my Catalina. The starter battery charges up to 13+ volts and holds there rather well. The house batteries charge up to a slightly lower voltage. (BTW - these are big batteries - I forget the group but they are approximately 16" long by 12" wide - they are also less than 3 months old.)

Here is my problem. Tonight we went over from our dock to the fuel dock for fuel. The only draw on the house batteries was from our Raymarine ST50 gear - maybe 2 to 3 amps according to the ammeter. We ran the boat about .3 hours - based upon the engine hour meter. When we returned to our dock the voltage reading with all circuts off on the house bank was about 12.2 or 12.3 volts. This seems very low to me. I checked to see if something was drawing on the batteries but the ammeter said no - 0 AMPS.

My question - what voltages are considered to be 75%, 50%, and 25% charged presuming that there is no load on the battery and it has had a few minutes to recover from the previous load.
svzephyr44 is offline  
Quote Share with Facebook
For the best viewing experience please update your browser to Google Chrome