please tell me if my battery charging is ok?

[David J Smith]

Hi guys. In brief to start with. Early this year I replaced my four massive 160 ah batteries. (The same as I had fitted previous). Along with a brand-new alternator. The engine is a Barrus Shire. When I start cruising. I get a reading of 14.2 volts. Which I guess proves the alternator is working. We cruise for around five hours. When we park up for the night. I noticed that it reads 12.9 volts. This is pretty constant every day.  But it's reading that well before we switch some internal lights on. Which are all LED by the way. My inverter is 3kw.  after we have sat down for the evening. I checked the voltage after an hour, and it dropped to 12.7. The only other thing on in the boat is the 12-volt fridge. Are these readings ok? Because I know that the lights will go on a lot sooner this time of year. Please tell me what it should read, and/or put my mind at rest please.

Thanks David. N/B Tickertboo. (presently near Rugby)

[Alan de Enfield]

As a battery comes 'off charge' it could show 13 or 14 volts, but that is just 'surface charge' as the surface charge is absorbed  the voltage drops.

After a couple of hours disconnected from the charger, and with nothing using 'leccy, the battery will show 12.7-12.8v

 

A fully charged battery should show 12.7 volts.

 

 

 

[magnetman]

It sounds fine to me. 

 

The best time to check battery voltage is in the morning before running engine or getting any solar input (if fitted). 

 

 

[David J Smith]

34 minutes ago, David J Smith said:

Hi guys. In brief to start with. Early this year I replaced my four massive 160 ah batteries. (The same as I had fitted previous). Along with a brand-new alternator. The engine is a Barrus Shire. When I start cruising. I get a reading of 14.2 volts. Which I guess proves the alternator is working. We cruise for around five hours. When we park up for the night. I noticed that it reads 12.9 volts. This is pretty constant every day.  But it's reading that well before we switch some internal lights on. Which are all LED by the way. My inverter is 3kw.  after we have sat down for the evening. I checked the voltage after an hour, and it dropped to 12.7. The only other thing on in the boat is the 12-volt fridge. Are these readings ok? Because I know that the lights will go on a lot sooner this time of year. Please tell me what it should read, and/or put my mind at rest please.

Thanks David. N/B Tickertboo. (presently near Rugby)

 

Thanks, Alan and Magnetman. That has really put my mind at rest. Cheers for your fast answers guy.

David.

[blackrose]

5 hours ago, magnetman said:

The best time to check battery voltage is in the morning before running engine or getting any solar input (if fitted). 

 

...with no charge or discharge to/from the batteries. So you'd need to make sure everything is switched off including your 12v fridge.