Battery charging, with 12V sockets and a multimeter

[smileypete]

My batteries are 2 x long life, deep cycle, AGM sealed 125Ah batteries. I am currently using a 12w solar panel that I clip on to the batteries with crocodile clips. I am intending to buy a 100w solar panel for a permanent set up, hopefully in the next few weeks.

 

 

Battery capacity 250Ah

Charged voltage 13.2v

tail current 04.0%

Charged detection time 03 mins

Charge efficiency factor 095%

 

Thanks Pete

 

For AGMs being charged by alt or solar I'd set it to:

 

Battery capacity 250Ah

Charged voltage 14.1v

tail current 2.0%

Charged detection time 03 mins

Charge efficiency factor 85%

 

Better for it to be little pessimistic about SoC than way too optimistic.

 

When the batts are at 'resting voltage', the reading can be used to determine SoC, and so double check the SoC reading on the gauge, using the table linked to in this post:

 

http://www.canalworld.net/forums/index.php?showtopic=69564&p=1386288

 

Also there's a link to the victron AGM data sheet which shows what the charge voltages can be set to for solar and shoreline charging etc.

 

If you're out cruising and off grid for a while, let us know how it's going when you can compare the indicated SoC. to the 'resting voltage' SoC (derived using the table.)

 

cheers, Pete.

~smpt~

Edited September 1, 2014 by smileypete

[dontpanic]

 

If you're out cruising and off grid for a while, let us know how it's going when you can compare the indicated SoC. to the 'resting voltage' SoC (derived using the table.)

 

Thanks Pete will do.

 

If I am able to get on to hook up and charge my batteries via my battery charger about once a week should I switch between charge voltages or stick with solar and alt as that will my main source of charge?

 

Many thanks Mel

[smileypete]

 

Thanks Pete will do.

 

If I am able to get on to hook up and charge my batteries via my battery charger about once a week should I switch between charge voltages or stick with solar and alt as that will my main source of charge?

 

Many thanks Mel

 

There's a link to a data sheet for Victron AGMs here, plus some thoughts on what charge voltage to use, if it's clear as mud just ask:

 

http://www.canalworld.net/forums/index.php?showtopic=69564&p=1386288

 

cheers, Pete.

~smpt~

[dontpanic]

Thanks Pete for all your advise really appreciated.

 

Mel