Attached is a diagram of how I think I want to connect my new solar panel, new charger controller, and new 1-2-both switch. I have a 9.9 Tohatsu (Nissan) outboard that also is in the mix. My question, other than general reactions to what I'm drawn, is will the solar output cause any problems with the outboard alternator? Are there any other problems you see? I'm a DC neophyte, so suggestions beyond using adequate gauge marine tinned wire would be most appreciated.
Electrical diagram - need input
- Thread starter Rich L
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- Jan 22, 2008
- 519
I'm no electrical guru
but from your diagram, your # 2 battery (the one on the right), would only charge when the switch is on 2 or both. (unless you missed labeling an 'off' option in which case only the number 1 (left) battery would charge) Is that what you want? Also when your outboard is running, it will only charge both batteries, if both are selected with your switch. Otherwise, again, only your nuber 1 will charge. If your switch has an off function, and that is selected while you are away from the boat, then only your number 1 battery will charge. I cannot comment on your alternator question, because I don't know. My suggestion would be to have your solar charger + and - go directly to the charge controller + and - respectively as you do now, and then to the + and - of each battery bypassing the 1 2 both switch. This way, both batteries will charge from the solar panel, even when your switch is off, and thereby cutting current to anything else on your boat, including your motor. As I read your diagram, your whole boat's electrical system is live, whenever you are charging with the solar panel, because you have to have at least one or both batteries selected to have them charging. Your outboard is live as well, ready for someone to push the start switch and off with your boat.
but from your diagram, your # 2 battery (the one on the right), would only charge when the switch is on 2 or both. (unless you missed labeling an 'off' option in which case only the number 1 (left) battery would charge) Is that what you want? Also when your outboard is running, it will only charge both batteries, if both are selected with your switch. Otherwise, again, only your nuber 1 will charge. If your switch has an off function, and that is selected while you are away from the boat, then only your number 1 battery will charge. I cannot comment on your alternator question, because I don't know. My suggestion would be to have your solar charger + and - go directly to the charge controller + and - respectively as you do now, and then to the + and - of each battery bypassing the 1 2 both switch. This way, both batteries will charge from the solar panel, even when your switch is off, and thereby cutting current to anything else on your boat, including your motor. As I read your diagram, your whole boat's electrical system is live, whenever you are charging with the solar panel, because you have to have at least one or both batteries selected to have them charging. Your outboard is live as well, ready for someone to push the start switch and off with your boat.
Solar directly to batteries
I like that idea, so that the OFF position on the 1-2-Both switch would switch off the current to the motor. I also realized that I need a couple of fuses near the batteries on the positive poles. Regarding your first couple of paragraphs where you mention that only the number 1 battery charges unless I have the switch on Both, I thought I would generally cruise with the switch in the Both position. I have a battery combiner, but can't figure how I would integrate it into this drawing. I guess I need more help. Any more ideas?
I like that idea, so that the OFF position on the 1-2-Both switch would switch off the current to the motor. I also realized that I need a couple of fuses near the batteries on the positive poles. Regarding your first couple of paragraphs where you mention that only the number 1 battery charges unless I have the switch on Both, I thought I would generally cruise with the switch in the Both position. I have a battery combiner, but can't figure how I would integrate it into this drawing. I guess I need more help. Any more ideas?
according to your diagram
your solar charge controller has no negative lead from the panel. all controllers I have seen have both leads from the panel going into it, then the negative goes to the bus or battery. You should not need the external blocking diode, the controller should disconnect the panel when it is not producing current. Why the positive lead from the controller to the positive bus AND the positive to the #1 battery? I would recommend that both leads from the panel gop to the controller, then both leads from the controller to one battery and a combiner between the two batteries. No, the solar will not affect your outboard alternator at all. Are the batteries one house and one for starting? or just 2 batteries for both? Your diagram shows both batteries used for house and starting.
your solar charge controller has no negative lead from the panel. all controllers I have seen have both leads from the panel going into it, then the negative goes to the bus or battery. You should not need the external blocking diode, the controller should disconnect the panel when it is not producing current. Why the positive lead from the controller to the positive bus AND the positive to the #1 battery? I would recommend that both leads from the panel gop to the controller, then both leads from the controller to one battery and a combiner between the two batteries. No, the solar will not affect your outboard alternator at all. Are the batteries one house and one for starting? or just 2 batteries for both? Your diagram shows both batteries used for house and starting.
response to Reudi's questions
REUDI - SEE CAPS your solar charge controller has no negative lead from the panel. all controllers I have seen have both leads from the panel going into it, then the negative goes to the bus or battery. THIS CONTROLLER DOESN'T HAVE A NEGATIVE INPUT FOR THAT TYPE OF SET UP. THE LEFT MOST TERMINALS ON THE CONTROLLER ARE POSITIVE IN AND POSITIVE OUT. THE MIDDLE TWO TERMINALS ARE TO RUN A LIGHT LOAD WHEN THERE IS OVERFLOW FROM THE BATTERIES, BUT IT IS OPTIONAL AND NOT NEEDED IN MY SET UP BECAUSE I SIZED THE SOLAR PANEL SO THAT THIS WILL NOT BE NEEDED. You should not need the external blocking diode, the controller should disconnect the panel when it is not producing current. THIS CONTROLLER RECOMMENDS IT - I WAS SURPRISED, TOO! Why the positive lead from the controller to the positive bus AND the positive to the #1 battery? THIS CONTROLLER HAS TWO SENSING WIRES THAT DIRECTLY MONITOR THE BATTERY CONDITION, SO IT REQUIRES THE TWO WIRES ON THE RIGHT COMING OUT OF THE CONTROLLER TO BE WIRED DIRECTLY TO THE BATTERY POSTS OF ONE OF THE BATTERIES. I would recommend that both leads from the panel go to the controller, then both leads from the controller to one battery and a combiner between the two batteries. No, the solar will not affect your outboard alternator at all. WONDERFUL - THANKS! Are the batteries one house and one for starting? or just 2 batteries for both? Your diagram shows both batteries used for house and starting. I WAS TRYING TO WIRE IT SO THAT THE 1-2-Both SWITCH WOULD DICTATE WHETHER THE STARTER, HOUSE, OR BOTH WOULD DRAW ON #1 BATTERY, #2 BATTERY OR BOTH. WHEN I'M DOING WEEKEND TRIPS, I HAVE TONS OF CAPACITY AND WOULD JUST LEAVE IT ON BOTH. WHEN I DO WEEK-LONG TRIPS, I WOULD DRAW DOWN ONE BATTERY AND THEN THE OTHER SO THAT I WOULD KNOW WHERE I STAND WHEN ONE BATTERY NO LONGER TURNS OVER THE MOTOR. THANKS REUDI! I'M INTERESTED IN SUGGESTIONS !
REUDI - SEE CAPS your solar charge controller has no negative lead from the panel. all controllers I have seen have both leads from the panel going into it, then the negative goes to the bus or battery. THIS CONTROLLER DOESN'T HAVE A NEGATIVE INPUT FOR THAT TYPE OF SET UP. THE LEFT MOST TERMINALS ON THE CONTROLLER ARE POSITIVE IN AND POSITIVE OUT. THE MIDDLE TWO TERMINALS ARE TO RUN A LIGHT LOAD WHEN THERE IS OVERFLOW FROM THE BATTERIES, BUT IT IS OPTIONAL AND NOT NEEDED IN MY SET UP BECAUSE I SIZED THE SOLAR PANEL SO THAT THIS WILL NOT BE NEEDED. You should not need the external blocking diode, the controller should disconnect the panel when it is not producing current. THIS CONTROLLER RECOMMENDS IT - I WAS SURPRISED, TOO! Why the positive lead from the controller to the positive bus AND the positive to the #1 battery? THIS CONTROLLER HAS TWO SENSING WIRES THAT DIRECTLY MONITOR THE BATTERY CONDITION, SO IT REQUIRES THE TWO WIRES ON THE RIGHT COMING OUT OF THE CONTROLLER TO BE WIRED DIRECTLY TO THE BATTERY POSTS OF ONE OF THE BATTERIES. I would recommend that both leads from the panel go to the controller, then both leads from the controller to one battery and a combiner between the two batteries. No, the solar will not affect your outboard alternator at all. WONDERFUL - THANKS! Are the batteries one house and one for starting? or just 2 batteries for both? Your diagram shows both batteries used for house and starting. I WAS TRYING TO WIRE IT SO THAT THE 1-2-Both SWITCH WOULD DICTATE WHETHER THE STARTER, HOUSE, OR BOTH WOULD DRAW ON #1 BATTERY, #2 BATTERY OR BOTH. WHEN I'M DOING WEEKEND TRIPS, I HAVE TONS OF CAPACITY AND WOULD JUST LEAVE IT ON BOTH. WHEN I DO WEEK-LONG TRIPS, I WOULD DRAW DOWN ONE BATTERY AND THEN THE OTHER SO THAT I WOULD KNOW WHERE I STAND WHEN ONE BATTERY NO LONGER TURNS OVER THE MOTOR. THANKS REUDI! I'M INTERESTED IN SUGGESTIONS !
See the Solar Post, too
Rich Hope you read the solar post going on at this same time. Many of the same comments and questions. Stu
Rich Hope you read the solar post going on at this same time. Many of the same comments and questions. Stu
- Jan 22, 2008
- 519
a combiner
is essentially a diode gate which allows both batteries to charge, but only one to discharge. I have one in a stink pot I once owned. When the motor ran, both charged, but when not, only the house batt was discharging, leaving the starting batt fresh for a motor start, when I had drained the other with the radio. They are relatively cheap as I recall, and link between the two batteries. They come with a wiring diagram.
is essentially a diode gate which allows both batteries to charge, but only one to discharge. I have one in a stink pot I once owned. When the motor ran, both charged, but when not, only the house batt was discharging, leaving the starting batt fresh for a motor start, when I had drained the other with the radio. They are relatively cheap as I recall, and link between the two batteries. They come with a wiring diagram.
It should work
The diagram you posted should work fine, as long as the controller is as you describe. One thing to note is that the alternator and the panel are connected directly to the load bus, while the batteries are connected through the switch. If you were to turn the battery switch to off while the panel and/or alternator were putting out, the voltage and the load bus could rise to the point where it could damage something. The panels typically put out about 17 volts and I think the outboard alternator will put out even higher voltages under light load. Bottom line, never turn the battery switch to off and you will be fine.
The diagram you posted should work fine, as long as the controller is as you describe. One thing to note is that the alternator and the panel are connected directly to the load bus, while the batteries are connected through the switch. If you were to turn the battery switch to off while the panel and/or alternator were putting out, the voltage and the load bus could rise to the point where it could damage something. The panels typically put out about 17 volts and I think the outboard alternator will put out even higher voltages under light load. Bottom line, never turn the battery switch to off and you will be fine.
It should work
Thinking more about it, the solar controller will limit the voltage from the panels, so the only thing you have to worry about is overvoltage from the alternator. However, when I disconnect the batteries from the output of my solar controller, it goes into the 'buzz' mode, as the voltage rises, making the contacts open, making the voltage fall, making the contacts close, etc., about 30 times a second. Not the end of the world, but it does probably wear out the relay faster.
Thinking more about it, the solar controller will limit the voltage from the panels, so the only thing you have to worry about is overvoltage from the alternator. However, when I disconnect the batteries from the output of my solar controller, it goes into the 'buzz' mode, as the voltage rises, making the contacts open, making the voltage fall, making the contacts close, etc., about 30 times a second. Not the end of the world, but it does probably wear out the relay faster.
Kewl - solar charger diagram
Don - Thanks for the input. I was thinking that the only time I would turn off the 1-2-Both switch was when I was away from the boat so that no one could get power to the motor by by-passing the ignition key switch and steal the boat. I would take down the solar panel (has a quick-disconnect and two thumb screws)so that they couldn't steal that either. So it sounds like I'm in business! The ideas here are very helpful. My only problem is that I have a battery combiner and no where to use it!
Don - Thanks for the input. I was thinking that the only time I would turn off the 1-2-Both switch was when I was away from the boat so that no one could get power to the motor by by-passing the ignition key switch and steal the boat. I would take down the solar panel (has a quick-disconnect and two thumb screws)so that they couldn't steal that either. So it sounds like I'm in business! The ideas here are very helpful. My only problem is that I have a battery combiner and no where to use it!
Use the combiner
...and leave your battery switch off and the panel connected while you're away from your boat. Why let all that good
go to waste? It'll offset the self-discharge of your batteries if you have wet cells, and your batteries will always be topped off when you return to the boat. Just lock your solar panel onto the boat, too. We did that with a shot length of wire pennant with loops at each end and a lock. Since solar only adds a little to your charge everyday, make use of the sun when you're gone, your batteries will last longer. Stu
...and leave your battery switch off and the panel connected while you're away from your boat. Why let all that good
go to waste? It'll offset the self-discharge of your batteries if you have wet cells, and your batteries will always be topped off when you return to the boat. Just lock your solar panel onto the boat, too. We did that with a shot length of wire pennant with loops at each end and a lock. Since solar only adds a little to your charge everyday, make use of the sun when you're gone, your batteries will last longer. StuCombiner is not a diode isolator
From West Marine ad for a combiner "Our voltage-sensing Battery Combiner relays connect two batteries during charging to ensure even energy replenishment, yet isolates the batteries during use, so both banks are not discharged." If I understand the usual terminology, an isolator is a diode array and a combiner is a voltage controlled relay. I am aware that language and terminology is changed from time to time but this is my understanding of the common usage of these terms. A diode array (isolator) could serve the same purpose as a voltage controlled relay (combiner). Just so those who go to West Marine and buy a combiner will know what they are getting. Either system will have some energy loss. The diodes from their band gap resistance and the relay from the current needed to hold it active. I do not know for certain how they would really compare in this application but I suspect the combiner would be more efficient. A mechanical contact will have lower resistance but is more subject to failure than a diode system. The diode array would probably serve better to protect and isolate the other sources of electrcal energy.
From West Marine ad for a combiner "Our voltage-sensing Battery Combiner relays connect two batteries during charging to ensure even energy replenishment, yet isolates the batteries during use, so both banks are not discharged." If I understand the usual terminology, an isolator is a diode array and a combiner is a voltage controlled relay. I am aware that language and terminology is changed from time to time but this is my understanding of the common usage of these terms. A diode array (isolator) could serve the same purpose as a voltage controlled relay (combiner). Just so those who go to West Marine and buy a combiner will know what they are getting. Either system will have some energy loss. The diodes from their band gap resistance and the relay from the current needed to hold it active. I do not know for certain how they would really compare in this application but I suspect the combiner would be more efficient. A mechanical contact will have lower resistance but is more subject to failure than a diode system. The diode array would probably serve better to protect and isolate the other sources of electrcal energy.
,Combiner and Diode Isolator
Rick, As I understand it, an isolator such as the Pathmaker does consume current (amps) when energized but a diode isolator results in a voltage drop. Since an isolator is only engaged in the presence of charging source, current loss IMHO not a significant issue, while a voltage drop could be problematic for voltage sensitive devices or electronics as well as charge regulators. Good Luck!
Rick, As I understand it, an isolator such as the Pathmaker does consume current (amps) when energized but a diode isolator results in a voltage drop. Since an isolator is only engaged in the presence of charging source, current loss IMHO not a significant issue, while a voltage drop could be problematic for voltage sensitive devices or electronics as well as charge regulators. Good Luck!
Looks good
The diagram looks like it would work ok, if you are worried about the solar power getting back into the outboard, just add a diode like the solar panel has. This is the reason for the solar diode, to keep the battery from destroying the panel. If you add a diode make sure the amp rating for the diode is greater than the outboard output current. I would say you probably don't need a diode since the outboard is always connected directly to the battery, which would be the same as being connected to the solar panel. Diodes typically will drop the voltage .6v, not enough to worry about. Good luck
The diagram looks like it would work ok, if you are worried about the solar power getting back into the outboard, just add a diode like the solar panel has. This is the reason for the solar diode, to keep the battery from destroying the panel. If you add a diode make sure the amp rating for the diode is greater than the outboard output current. I would say you probably don't need a diode since the outboard is always connected directly to the battery, which would be the same as being connected to the solar panel. Diodes typically will drop the voltage .6v, not enough to worry about. Good luck
Further thought
If you used a battery isolator (sold at auto stores) in place of your battery switch both batteries would charge automatically, without draining from each other. First you would replace your battery switch with the isolator. Then the load lines from the + batteries would then be connected to the 1-2 posts on the now unused switch and the output would go to the house, not connecting to the + buss as shown in the diagram.
If you used a battery isolator (sold at auto stores) in place of your battery switch both batteries would charge automatically, without draining from each other. First you would replace your battery switch with the isolator. Then the load lines from the + batteries would then be connected to the 1-2 posts on the now unused switch and the output would go to the house, not connecting to the + buss as shown in the diagram.
Electrical Diagram - battery draw down?
Terry - with your suggestion: 1. both batteries are used to start the engine 2. I can choose which battery I use for the house supply, thereby conserving one battery for battery starting. Looks like a better idea. Thanks!
Terry - with your suggestion: 1. both batteries are used to start the engine 2. I can choose which battery I use for the house supply, thereby conserving one battery for battery starting. Looks like a better idea. Thanks!
Better electrical suggestion
I think I like this diagram even better. Terry's idea made me think of it. This allows me to charge both batteries from the solar charger by using a combiner (between the batteries) regardless of the position of the 1-2-Both switch, plus let's me decide which battery to use for my electrical needs. I have a small boat (26'), so my electrical needs are also small. I'm still open to ideas, but this is starting to look pretty good to me. Please note that the sensing wires coming off the Charge Controller must be attached directly to the battery posts. I put a 40A fuse on each primary positive wire to stop any direct shorts. Both batteries are identical type and age. Thanks for you ideas.
I think I like this diagram even better. Terry's idea made me think of it. This allows me to charge both batteries from the solar charger by using a combiner (between the batteries) regardless of the position of the 1-2-Both switch, plus let's me decide which battery to use for my electrical needs. I have a small boat (26'), so my electrical needs are also small. I'm still open to ideas, but this is starting to look pretty good to me. Please note that the sensing wires coming off the Charge Controller must be attached directly to the battery posts. I put a 40A fuse on each primary positive wire to stop any direct shorts. Both batteries are identical type and age. Thanks for you ideas.
Battery sense wires
What if say battery #2 is discharged and the solar sense + wire is connected to battery #1 +, and this battery is charged? The battery combiner works by looking for a charge input on either battery and then shorts the batteries together via a relay contact to charge both batteries. If the solar regulator thinks the batteries are charged, looking at #1, it produces no output to activate the combiner. This is why in my diagram I had the sense on the + buss looking at both batteries thru the isolator. The reason for putting the sense wires directly on the battery is to get a actual battery voltage. If your wire and connections from the + buss to the batteries is as good or better than the sense wires, wire is wire, it would know no difference. The isolator would have a .6v voltage drop from the + sense side to the battery side, so your batteries could conceivably be .6v higher than the sense side. Gook Luck
What if say battery #2 is discharged and the solar sense + wire is connected to battery #1 +, and this battery is charged? The battery combiner works by looking for a charge input on either battery and then shorts the batteries together via a relay contact to charge both batteries. If the solar regulator thinks the batteries are charged, looking at #1, it produces no output to activate the combiner. This is why in my diagram I had the sense on the + buss looking at both batteries thru the isolator. The reason for putting the sense wires directly on the battery is to get a actual battery voltage. If your wire and connections from the + buss to the batteries is as good or better than the sense wires, wire is wire, it would know no difference. The isolator would have a .6v voltage drop from the + sense side to the battery side, so your batteries could conceivably be .6v higher than the sense side. Gook Luck
Wire is wire
I guess I was being too anal retentive on following the directions. I guess I can't argue with "wire is wire". I plan on making good crimped, soldered, and waterproofed connections. Thanks for your good counsel.
I guess I was being too anal retentive on following the directions. I guess I can't argue with "wire is wire". I plan on making good crimped, soldered, and waterproofed connections. Thanks for your good counsel.
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