>>3 Battery PONTOON BOAT - Trickle / maintenance ‘SOLAR charging kit’ setup help!!!

[SparkyGage]

The boat is going to be kept and is kept in a 40 foot storage unit and a storage facility…
it has a ‘Perko’ switch which twin turned to the opposition, completely disconnects all power from the three batteries for anything.

The switch has ‘OFF’ ‘Position 1’ ( main starter battery ) ‘Position 2’ ( the other 2 batteries powering stereo) ‘ALL’ (all 3 batteries which I have it on when on the water and moving. ‘position 2’ when in. a cove or beach at the lake listening to music.

Ok, so where are you planning to mount a panel?

 

[Leonvilj]

the 2 charge controller in the boat under ttthe seat by the batteries. the 2 - 100 watt panels outside the storage unit next to the door on the wall as I have seen other do. I will just run the cord under the storage door or inside an opening

 

[SparkyGage]

Ok, two batteries (B1, B2) sit next to each other all the time and B3 is some distance away.

*If it was me*:

• I would have B1 and B2 in parallel (as "bank1")and B3 as reserve ("bank2")on a manual switch unless I can figure a way to move them together since running parallel at random distances can be an issue. I'd have a separate voltage level indicator for each bank.
• A charge controller for the pair and one for the reserve (i.e. each bank). Each charge controller connected the same way the bank is connected to the boat (Bank1 B1+ to boat Positive and B2- to boat Negative, Bank2 B3 wired normal.)
• I would put some type of circuit breaker (mainly to act as a switch) between the connector for the solar panels and the charge controllers so I know there won't be a spark with I connect or disconnect them.
• Lastly, If I'm running 2 banks, I would randomly run on the reserve to exercise the battery. Switch to reserve when I know I am coming in for the day.

My biggest concern is having a large and random distance between batteries in parallel. It may work, but it's something I would be nervous about. And if I have the batteries, setting one up as a reserve is a nice safety feature.

 

[Leonvilj]

Ok, two batteries (B1, B2) sit next to each other all the time and B3 is some distance away.

*If it was me*:

• I would have B1 and B2 in parallel (as "bank1")and B3 as reserve ("bank2")on a manual switch unless I can figure a way to move them together since running parallel at random distances can be an issue. I'd have a separate voltage level indicator for each bank.
• A charge controller for the pair and one for the reserve (i.e. each bank). Each charge controller connected the same way the bank is connected to the boat (Bank1 B1+ to boat Positive and B2- to boat Negative, Bank2 B3 wired normal.)
• I would put some type of circuit breaker (mainly to act as a switch) between the connector for the solar panels and the charge controllers so I know there won't be a spark with I connect or disconnect them.
• Lastly, If I'm running 2 banks, I would randomly run on the reserve to exercise the battery. Switch to reserve when I know I am coming in for the day.

My biggest concern is having a large and random distance between batteries in parallel. It may work, but it's something I would be nervous about. And if I have the batteries, setting one up as a reserve is a nice safety feature.

this is great… Makes sense gonna try and go with the set up in a couple weeks when I go back to the storage unit. stay tuned.

One last question with all of the equipment listed above I’m going to get including the Victron 7515 two of those… Does 10 AWG wire work from the panels to the charge controllers and the charge controllers to the batteries? it seems from what I’ve been reading. It’s a better option than 12 AWG.!?

 

[Partimewages]

10 is probably better if the runs are over 10' and under 40. Count wire length both ways.

 

[Leonvilj]

10 is probably better if the runs are over 10' and under 40. Count wire length both ways.

from the first solar panel outside the storage unit to the first solar charge controller in the boat under the backseat in the storage unit will be about 35 feet… From the second solar panel again outside the storage unit to the second charge controller the same it will be about 35 feet for both wires from the solar panel to the controller
The wires from the charge controller to the batteries is going to be about 2 feet at most

 

[Partimewages]

Here's a link for a voltage drop calculator.

Voltage Drop Calculator | Southwire

www.southwire.com

It will help you determine what size exactly you need for all your wire runs. This will be easier to change.

 

[SparkyGage]

10 or 8 to reduce loss. If you ever touch the wire and it's warmer than ambient, you have a problem.

I would run each panel to one of these mounted inside the shed: https://www.amazon.com/Miniature-Circuit-Isolator-Magnetic-Disconnect/dp/B09BQR289J then run the cable to your boat charger. That way you could disconnect without even touching the boat (shock).

This https://www.amazon.com/Extension-Silicone-Battery-Portable-Generator/dp/B0BX5ZXK8J could give you the quick disconnect you need. It has a male and female, so cut it about 1-2 feet from the Female end and attach the cut to the switch. Attach the cut with the male to the charger controller. Now you have a manufactured quick connection that should be secure. Whether you put the long cord on the switch or boat side is up to you, but for my own use, I would rather have the long one on the boat and stow it.

Also: GET 24V NOT 12V PANELS. It's easy to be thinking "I'm using 12v batteries, I need a 12v panel". Remember the charge controller, converts greater than 12 volts down to a regulated 12v (actually just over, but it should be the "ideal"). I think the Victron you were looking at can take up to 75v? Greater voltage, mean fewer amps, which means less loss which, means less heat and less shock risk. (I'm a safety nut with boats: I enjoy sailing, enjoy the water, hate fire other than camping on an island, and I'm really not a fan of drowning.)