Am I killing my batteries?

[kev_rm]

One of the benefits of a solar panel system is the ability to charge the batteries when the boat is stored without cooking them. With two 140 watt panels and 12 Trojan 105 six volt batteries the two solar panels more than charged the batteries. (Caribbean summer sun) so I had to make a cover to block half of the panels.

Batteries now stay at about 12.6 volts and water is needed to be added once in seven months of storage.

I am assuming you are talking about just maintaining them at float vs. actually charging them.

200 amp hours = 1.2KWH = 4+ hours full sunlight on two panels *per battery*.

Edit: Also, your charger should not need you to block a panel in any case... its got bad internal logic if you have to reduce input.

 

[Bay Pelican]

I am assuming you are talking about just maintaining them at float vs. actually charging them.

200 amp hours = 1.2KWH = 4+ hours full sunlight on two panels *per battery*.

Edit: Also, your charger should not need you to block a panel in any case... its got bad internal logic if you have to reduce input.

You are right about the charger. I use the cover out of personnal preference. With two panels the voltage stays at 13+, whereas with one panel the voltage is 12.6.

I feel more comfortable with the 12.6.

Also I am generally very cautious. This way I have both the charge control and the canvas cover protecting against overcharging. The history is that for five years I had only one panel and all went well. Now I have two panels and I decided not to increase the summer charging.

Two days before I arrive I have someone take off the cover and the batteries are at 13+.

 

[Heron]

My Sterling 40 amp charger floats at 13V. I'm comfortable with that, and I'm sure my GC batteries are as well..

 

[Brooksie]

If your boat is in the water and not checked daily, turning your charging system off could be a big mistake. Have a hose pop off or another serious leak source and down she goes. A boat sank here even though the owner had all the valves shut off. The muskrat camping out in an exhaust tube chewed through the tube.

My boat has been on a mooring for 35 years, never a dockside charge or solar panel starts every week for a trip. A well found boat is in more danger being plugged in at a dock than shut down on a mooring. Don't be afraid to stop charging.

 

[LarryM]

The guys that are heavily into off grid stuff use adjustable chargers that you can set all four (including equalize) voltages as well as charge rates and you set it to to what the battery manufacturer recommends. Most chargers do not go high enough on absorption (sometimes needs to be 15+ volts) to get a really good charge.[/QUOTE

Right, the Mastervolt Chargemaster voltages are programmable from 0-15.5V for each charging stage. I was just commenting on the Factory Default settings which I assumed would be pretty conservative, but, we all know what assuming can lead to . . . . . .

 

[Art]

My boat has been on a mooring for 35 years, never a dockside charge or solar panel starts every week for a trip. A well found boat is in more danger being plugged in at a dock than shut down on a mooring. Don't be afraid to stop charging.

AGREED!!!

 

[MurrayM]

My boat has been on a mooring for 35 years, never a dockside charge or solar panel starts every week for a trip. A well found boat is in more danger being plugged in at a dock than shut down on a mooring. Don't be afraid to stop charging.

But, but, but...there are so many gizmo's to make things better!

Our boat goes on shore power in early November and gets unplugged at the end of March. (*Edit* We take Badger out for romps during the winter). That's mostly for heat in the engine room and a couple smaller heaters in the forward berth and saloon, but the batteries also get charged at the same time.



We don't have the time tested experience of Brooksie but so far, according to the SmartGauge, the farthest Badger's batteries have dropped all summer while tied to the dock was to 90%.

Time will tell...the batteries (6 volt golf cart) have only got two years under their plates.

 

[koliver]

But, but, but...there are so many gizmo's to make things better!

Our boat goes on shore power in early November and gets unplugged at the end of March. That's mostly for heat in the engine room and a couple smaller heaters in the forward berth and saloon, but the batteries also get charged at the same time.

We don't have the time tested experience of Brooksie but so far, according to the SmartGauge, the farthest Badger's batteries have dropped all summer while tied to the dock was to 90%.

Time will tell...the batteries (6 volt golf cart) have only got two years under their plates.

Similar here: When not in use, my boat is plugged in at the dock. For the winter, it is checked roughly once a month, but so far, in 22 years, nothing has needed to be changed upon checking. My last set of batteries died of old age at 10 years for the 6v Golf cart Lead Acid house and at 12 yrs for the 4D Start battery. No solar panels, charging through a Xantrex MS2000 Inverter/charger, so always on.

 

[JDCAVE]

The float charge should vary with temperature. My float charge was over 14 volts in the winter, so I phoned Magnum to find out what was going on. The Tech explained that the temperature sensor provides information to allow for temperature compensation of float charge. We turn our solar panels off in the winter, relying on the Magnum 2812 to make all the "decisions".