I currently have 1 starter battery connected to outboard and 1 house battery connected to charger and inverter. I want to parallel an add'l house battery. Now for the schematic questions: 1. does the term paralleling mean connecting the +'s together and the (-) together? 2. if I purchased a combiner, can I use the existing charger to charge the (new 2 house battery bank? 3. if my thinking is correct, what combiner do I need; Heart interface pathmaker, Xantrex, etc?
- Status
a simple solution
Jeff: A parallel hookup would indeed involve hooking positivie to positive and negative to negative. This arrangement keeps the voltage at 12, whereas hooking the two batteries "in series" would raise the voltage to 24. For only two batteries, I would probably just hook wire the batteries together without investing in a combiner. Simply wiring the batteries together would allow you to charge both batteries simultaneously. If you want to invest in a more sophisticated system, I would purchase a battery switch rather than a combiner.
Jeff: A parallel hookup would indeed involve hooking positivie to positive and negative to negative. This arrangement keeps the voltage at 12, whereas hooking the two batteries "in series" would raise the voltage to 24. For only two batteries, I would probably just hook wire the batteries together without investing in a combiner. Simply wiring the batteries together would allow you to charge both batteries simultaneously. If you want to invest in a more sophisticated system, I would purchase a battery switch rather than a combiner.
Battereis
Jeff, What size is your outboard? If it is small enough to crank by hand you really don't need a dedicated engine battery. I use a Honda 9.9 and have two group 24 batteries hooked in parallel which provide about 170 amp-hours of storage on my 26 footer. I have had the two batteries in parallel for years and charge them from the motor or a built-in charge when hooked to shore power. I also have a 30 watt solar panel to keep them topped up when the boat's on the trailer. David Las Vegas
Jeff, What size is your outboard? If it is small enough to crank by hand you really don't need a dedicated engine battery. I use a Honda 9.9 and have two group 24 batteries hooked in parallel which provide about 170 amp-hours of storage on my 26 footer. I have had the two batteries in parallel for years and charge them from the motor or a built-in charge when hooked to shore power. I also have a 30 watt solar panel to keep them topped up when the boat's on the trailer. David Las Vegas
Your Getting Good Advice!
Jeff, David & Mike have given you good advice. Just parrallel the new batteries as Mike described. An increase in house bank size (available AMP/HRS) will allow you to stay away from the dock longer. I assume from your description that house batteries are charged only at the dock via 110v charger/inverter. Although I am not familiar with capabilities of your engine alternator, I would look into a way to charge the house batteries when on the water This can be done in several ways. The most economical way would be to run all battery banks through a selector switch so that all batteries could receive some charge when needed. You will then be able to charge the house bank, charge the start battery or charge both banks depending on switch position. You can also start the engine with your house bank if the start battery go south on you. A combiner is not really necessary (only a convenience). You will also be able to easily turn everything off to protect against incidental discharge. Jon McClain
Jeff, David & Mike have given you good advice. Just parrallel the new batteries as Mike described. An increase in house bank size (available AMP/HRS) will allow you to stay away from the dock longer. I assume from your description that house batteries are charged only at the dock via 110v charger/inverter. Although I am not familiar with capabilities of your engine alternator, I would look into a way to charge the house batteries when on the water This can be done in several ways. The most economical way would be to run all battery banks through a selector switch so that all batteries could receive some charge when needed. You will then be able to charge the house bank, charge the start battery or charge both banks depending on switch position. You can also start the engine with your house bank if the start battery go south on you. A combiner is not really necessary (only a convenience). You will also be able to easily turn everything off to protect against incidental discharge. Jon McClain
Still challanged
Thanks for the input, no pun. If I follow correctly I connect the charger to an Off-1-Both-2 switch, connect the #1 to the starter battery, connect the #2 to the house bank. This should allow me to charge either individually using #1 or #2 or charge them all together using (both)? Then I get a regular on/off switch, wire it from the starter battery to the house bank. Leave the on/off switch turned (off) unless I need to switch it (on) to use the house batteries to start the engine should the starter battery fail. One more question. If I wire the house batteries in parallel and charge them together is there a chance of over charging one of the batteries thus burning it out? I think my charger is setup to charge only one battery. Jeff
Thanks for the input, no pun. If I follow correctly I connect the charger to an Off-1-Both-2 switch, connect the #1 to the starter battery, connect the #2 to the house bank. This should allow me to charge either individually using #1 or #2 or charge them all together using (both)? Then I get a regular on/off switch, wire it from the starter battery to the house bank. Leave the on/off switch turned (off) unless I need to switch it (on) to use the house batteries to start the engine should the starter battery fail. One more question. If I wire the house batteries in parallel and charge them together is there a chance of over charging one of the batteries thus burning it out? I think my charger is setup to charge only one battery. Jeff
You are Getting Close!
Kind of hard to describe in words but I'll give it a try. You really don't need the extra ON/OFF switch. If the batteries are connected (the BOTH Position), they act as one bank and all are charged. As for overcharging, the more battery capacity that you have, the less likely the possibility of over charging. If you don't have an overcharging problem now, you will not have one when you add more storage capacity. I will assume that your shorepower charger has at least a two stage charging cycle, so I see no problem. As for overcharging with the engine alternator, the same logic applies. More battery capacity means longer before possible overcharge. You can also monitor battery voltage with an installed voltmeter. It is difficult to describe in text, but if you will send me your Email address, I will sketch it out for you. jmcclain@southshorelabs.com Jon
Kind of hard to describe in words but I'll give it a try. You really don't need the extra ON/OFF switch. If the batteries are connected (the BOTH Position), they act as one bank and all are charged. As for overcharging, the more battery capacity that you have, the less likely the possibility of over charging. If you don't have an overcharging problem now, you will not have one when you add more storage capacity. I will assume that your shorepower charger has at least a two stage charging cycle, so I see no problem. As for overcharging with the engine alternator, the same logic applies. More battery capacity means longer before possible overcharge. You can also monitor battery voltage with an installed voltmeter. It is difficult to describe in text, but if you will send me your Email address, I will sketch it out for you. jmcclain@southshorelabs.com Jon
Repairs
After you get this all sorted out, go to your favorite book store and get (or order) "Boatowner's Mechanical and Electrical Manual" by Nigel Calder. It's 600 pages, hardback, of great information for any boater. Covers all boat systems with pictures and drawings,...not cheap, but worth it.
After you get this all sorted out, go to your favorite book store and get (or order) "Boatowner's Mechanical and Electrical Manual" by Nigel Calder. It's 600 pages, hardback, of great information for any boater. Covers all boat systems with pictures and drawings,...not cheap, but worth it.
At Ease is Right
Calder's book is the BEST $50 you can spend on your boat. Even better: it's only the first 78 pages you need to read about your electrical question. The rest is about the rest of your boat! Stu
Calder's book is the BEST $50 you can spend on your boat. Even better: it's only the first 78 pages you need to read about your electrical question. The rest is about the rest of your boat! Stu
- Status