I hope this is a simple question. I want to set up a solar panel to charge my batteries. The size, watts, amp usage, etc. is not important; it will be large enough that I will need a regulator. I have two batteries on a 1-2-both switch which I use for the house system. A third battery, on a separate on-off switch, is the starting battery. My question: how should I connect the solar panel to the batteries? I want all three to be charged. Should I run three separate cables, one to each battery positive-negative posts? Should I run cables to the 1-2-both and on-off switches? Should I use an ECHO charger from the house to the start battery? Should I install an isolator on-off switch in the solar cable when I am at dockside using the electic 3-phase battery charger? All the schematics that come with solar panel systems show a simple one panel to one battery hook up. I am confused how to properly connect my disparate system and appreciate any and all feedback. Thanks.
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Just curious, but why do you have two separate house banks. It would make far more sense to have a single house bank of two batteries, rather than two house banks of one-battery each. There are many reasons for combining them, since the larger the house bank, the more efficient it will be.
As for how to set it up. I would recommend connecting it to the house bank and then using a battery combiner or echo charger to charge the starting bank.
You might want to have the solar panel charge regulator setup through a switch, so that you can disconnect it when using shore power.
As for how to set it up. I would recommend connecting it to the house bank and then using a battery combiner or echo charger to charge the starting bank.
You might want to have the solar panel charge regulator setup through a switch, so that you can disconnect it when using shore power.
Well im no expert but here is how I have mine wired up to 3 batteries," 1 start and 2 house banks" .
The panel has a controller, " 130 watt panel"btw". which is connected directly to the 2 batteries for house bank. My refridgeration is connected to the load output from charge controller. REasoning is that when the batteries get to 10.0 volts, the load is turned off so that you can start the engine and recharge.I also have a shore power charger that is connected to all 3 batteries. " charger has 3 seperate outputs and is capable of 20 AMP charge rate". I also do not understand why you have 2 seperate batties on another switch when the 2 batteries in parrralel will out perform and eliminate the switch. Leaving you with the batterie selector switch both-1-2, start battery , and house bank. I have 2 grp 27 batteries in parralel and have ran the ice box for 8 straight hours under sail with no problems or having to start engine.
The panel has a controller, " 130 watt panel"btw". which is connected directly to the 2 batteries for house bank. My refridgeration is connected to the load output from charge controller. REasoning is that when the batteries get to 10.0 volts, the load is turned off so that you can start the engine and recharge.I also have a shore power charger that is connected to all 3 batteries. " charger has 3 seperate outputs and is capable of 20 AMP charge rate". I also do not understand why you have 2 seperate batties on another switch when the 2 batteries in parrralel will out perform and eliminate the switch. Leaving you with the batterie selector switch both-1-2, start battery , and house bank. I have 2 grp 27 batteries in parralel and have ran the ice box for 8 straight hours under sail with no problems or having to start engine.
Chuck and Dog, I know what you're saying, but you overlook that you can parrallel the batteries with the "both" selection. The switch allows easy isolation of a suspected bad battery. The switch is already there, so use it.
Frank, you do not want to run a cable from the solar to each battery as that would be the same as strapping all threee batteries together.
Frank, you do not want to run a cable from the solar to each battery as that would be the same as strapping all threee batteries together.
http://blog.dankim.com/2009/02/02/solar-power-on-boats/
Good info about Solar Chargers, pay particular attention to using a MPPT controller to swaping E (voltage) for I (current), maximizes efficiency.
Good info about Solar Chargers, pay particular attention to using a MPPT controller to swaping E (voltage) for I (current), maximizes efficiency.
For the "ultimate" you need a separate regulator for each battery (or a regulator with multiple outputs/sense leads). But realistically, I'd hook it to the house battery switch since it's the house batteries that usually get discharged. Are you SURE you need to charge your starting battery? Why?
I just have clips on the solar-panel wires so I can hook it directly to the battery that needs charging, but mine is only 3A.
druid
I just have clips on the solar-panel wires so I can hook it directly to the battery that needs charging, but mine is only 3A.
druid
isolation/blocking diodes
I have a single 85W PV charging two banks of batteries through two Morningstar Sunsaver 10's. I tried it without any isolation diodes, but with the PV disconnected, I could still measure voltage on the input side of the controller, which concerned me and led me to this page from the Morningstar site:
http://www.morningstarcorp.com/en/support/library/ALL.APP.1_array_isolated_banks.01.EN.pdf
The idea is to make sure that voltage from one controller does not flow back 'upstream' (the diodes block this) such that a dead battery in one bank does not discharge a good battery in the other bank trying to get recharged.
I used big hunking diodes that I got a radio shack and an extra terminal bock to do it, so it was not expensive or hard... just had to keep my diagram in front of me. As I understand it, diodes allow flow in one direction, but not in the other direction. The current flows in the direction of the diode symbols which look like arrows. I believe there is a stripe on the downstream end of the physical diode.
Not sure how this applies to three battery systems. I suspect you just extend the diagram and use a third blocking diode.
BTW - all three of my charging sources - Balmer dual output alternator, 110v battery charger and Solar controller output are all full time hooked to the batteries through a fused lead, independent of the battery switch position. Each source must then have the ability to isolate the batteries. But it also means that switch position is independent of charging. I want to switch off when I leave the boat but continue to charge.
Edit - -one more thing - ignore the part of the diagram with the DC loads running off of the conroller.. that does not really apply to us, since we have multiple sources and multiple loads and want to switch between them... unless you want to use the low voltage disconnect feature for some individual load.
I have a single 85W PV charging two banks of batteries through two Morningstar Sunsaver 10's. I tried it without any isolation diodes, but with the PV disconnected, I could still measure voltage on the input side of the controller, which concerned me and led me to this page from the Morningstar site:
http://www.morningstarcorp.com/en/support/library/ALL.APP.1_array_isolated_banks.01.EN.pdf
The idea is to make sure that voltage from one controller does not flow back 'upstream' (the diodes block this) such that a dead battery in one bank does not discharge a good battery in the other bank trying to get recharged.
I used big hunking diodes that I got a radio shack and an extra terminal bock to do it, so it was not expensive or hard... just had to keep my diagram in front of me. As I understand it, diodes allow flow in one direction, but not in the other direction. The current flows in the direction of the diode symbols which look like arrows. I believe there is a stripe on the downstream end of the physical diode.
Not sure how this applies to three battery systems. I suspect you just extend the diagram and use a third blocking diode.
BTW - all three of my charging sources - Balmer dual output alternator, 110v battery charger and Solar controller output are all full time hooked to the batteries through a fused lead, independent of the battery switch position. Each source must then have the ability to isolate the batteries. But it also means that switch position is independent of charging. I want to switch off when I leave the boat but continue to charge.
Edit - -one more thing - ignore the part of the diagram with the DC loads running off of the conroller.. that does not really apply to us, since we have multiple sources and multiple loads and want to switch between them... unless you want to use the low voltage disconnect feature for some individual load.
Just remember that you will get a 3/4v drop across your diodes that will disapate heat, not a very efficient way of doing it, better to get a controller that will handle multiable banks, or multiple controllers.
Maximum Power Point Tracking (MPPT) is best,
expensive though.
Maximum Power Point Tracking (MPPT) is best,
expensive though.
What I got
I have three 85 watt panels, and one 65 watt. The 85's are led through one controller, and go to the battery selector switch. The 65 goes through a seperate controller, and is tied directly to the house bank. House bank is 4 6v golf cart batteries, total of 450ah. Have a plain ol toggle switch on each controller to allow them to be cut off if necessary.
When just sitting at the dock, with no shore power on, the battery selector switch is kept in the off position. This allows the house bank to be maintained by the single 65 watt panel. Only drain is the bilge pump. Rarely do I use the start/emergency battery, so I don't feel any need to keep it attached to a charge source, although I have considered an echo charger for it. This system works good for me. I know there are much more sophisticated and modern systems available, but this works, and follows the KISS principal.
I have three 85 watt panels, and one 65 watt. The 85's are led through one controller, and go to the battery selector switch. The 65 goes through a seperate controller, and is tied directly to the house bank. House bank is 4 6v golf cart batteries, total of 450ah. Have a plain ol toggle switch on each controller to allow them to be cut off if necessary.
When just sitting at the dock, with no shore power on, the battery selector switch is kept in the off position. This allows the house bank to be maintained by the single 65 watt panel. Only drain is the bilge pump. Rarely do I use the start/emergency battery, so I don't feel any need to keep it attached to a charge source, although I have considered an echo charger for it. This system works good for me. I know there are much more sophisticated and modern systems available, but this works, and follows the KISS principal.
Thanks. I think Nice-N-Easy's reply was the simplest and best, but all were helpful. In response to SaltyDog's query, my initial battery set-up that came with the boat was only two batteries, wired to the 1-2-both switch. I later added another battery to use as a dedicated starter for backup starting. There was already in place the on-off switch so the service yard connected it via that. This allows me to turn it off completely when at anchor or underway using the other two batteries to run the house systems. I can put the switch on "both" and they run together in parallel and do last longer (they are both AGM's with over 550 amp hour capacity) or I can select 1 or 2 separately.
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