I want to have two battery banks,I have two 12 volt deep cycle batteries now and want to add a 2nd bank, can I use two 6 volt batteries for bank two and will it charge from the same charger when I switch to 1 or 2 or is this not a good thing to do.
- Status
Yes, But what is your goal
12 Volt system (two 12v batteries in parallel), right ? The two 6 Volt batteries will go in serial, so the 2nd bank also has 12 volt output, right ? The short answer is "Yes" you can have the same charger. Creating a second battery bank might be more complicated then this, depending on what you want to accomplish. Maybe you could elaborate on why your adding a second battery bank / how your thinking of using it.
12 Volt system (two 12v batteries in parallel), right ? The two 6 Volt batteries will go in serial, so the 2nd bank also has 12 volt output, right ? The short answer is "Yes" you can have the same charger. Creating a second battery bank might be more complicated then this, depending on what you want to accomplish. Maybe you could elaborate on why your adding a second battery bank / how your thinking of using it.
Backup
I want to be able to switch to the second bank when 1st bank runs low while out sailing,I have lots of electric draw,ref,vhf,charplotter,radar,runs down the batteries when sailing and not running the engine,would switch to second bank before 1st bank runs too low. I would have just two banks and no start engine backup just switch between two banks.
I want to be able to switch to the second bank when 1st bank runs low while out sailing,I have lots of electric draw,ref,vhf,charplotter,radar,runs down the batteries when sailing and not running the engine,would switch to second bank before 1st bank runs too low. I would have just two banks and no start engine backup just switch between two banks.
The 1 - 2- ALL switch is for out put and
not best for running a charger through it. You can do what you suggest by running the two 12V batteries in parallel as one bank and the two 6 volts in serial as a second bank. I would suggest that to handle that serious storage capacity in an efficient manner that you also get one of those new smart chargers of 40 amps able to handle 1,2 or 3 Banks. The charger will feed the banks independently with priority to the weakest one irrespective of the setting of the output switch. Another recommendation would be that both the 12V batterise and the 6V batteries be similar in capacity and age as a weaker battery will drain the stronger one within that bank creating problems with the charging function. I run two 12V batteries each as a separate bank with a 20 Amp 3 cycle charger hard wired to each battery. The output is controlled by the usual switch but I never leave that switch in All to prevent a fouled Bank from draining the other. I also have a 1200 Watt inverter hard wired to my #2 bank which I mostly use as the house bank leaving #1 for starting duties and emergency backup. When overnighting a Honda 2000EU will usually bring both banks up on charge ready to do it all over again. Have never encountered a problem with this set up but had a hard time convincing my buddy to leave the switch in just 1 or 2 until one night his refrigerator killed both batteries and I had to lend them one of ours to get his boat started. Hope some of this will be of help.
not best for running a charger through it. You can do what you suggest by running the two 12V batteries in parallel as one bank and the two 6 volts in serial as a second bank. I would suggest that to handle that serious storage capacity in an efficient manner that you also get one of those new smart chargers of 40 amps able to handle 1,2 or 3 Banks. The charger will feed the banks independently with priority to the weakest one irrespective of the setting of the output switch. Another recommendation would be that both the 12V batterise and the 6V batteries be similar in capacity and age as a weaker battery will drain the stronger one within that bank creating problems with the charging function. I run two 12V batteries each as a separate bank with a 20 Amp 3 cycle charger hard wired to each battery. The output is controlled by the usual switch but I never leave that switch in All to prevent a fouled Bank from draining the other. I also have a 1200 Watt inverter hard wired to my #2 bank which I mostly use as the house bank leaving #1 for starting duties and emergency backup. When overnighting a Honda 2000EU will usually bring both banks up on charge ready to do it all over again. Have never encountered a problem with this set up but had a hard time convincing my buddy to leave the switch in just 1 or 2 until one night his refrigerator killed both batteries and I had to lend them one of ours to get his boat started. Hope some of this will be of help.
Thats great advice. I would also comment ...
Great advice from Benny. Note 1: don't be moving that battery switch while the engine is running, could ruin your alternator. Note 2: There should be few reasons to put the switch on BOTH (e.g. no other way to start engine). If you do put on both, remember to put it back to 1/2/ or OFF. Note 3: If you want to get a little fancier, add to Benny's solution a Blue-Sea battery combiner between battery bank #1 and #2, and connect your alternator directly to bank #1. The combiner will sense a charging voltage is present on Bank #1, and offer the power to Bank #2 simultaneously. When no charging voltage it will disconnect. Benefit, no matter your battery switch is on "1" or "2", your alternator will charge both batteries. It also helps you religiously avoid placing the switch in the BOTH position, which is bad for your batteries given the likely difference between their voltage potentials in the two banks. (also, with the alternator tied direct to bank #1, now you can move that battery switch while the engine is running) Note 4: None of these options are ideal, for getting the maximum life out of your batteries. For example, using your deep cycle to start your engine ... starter batteries are designed differently then house batteries for a reason.
Great advice from Benny. Note 1: don't be moving that battery switch while the engine is running, could ruin your alternator. Note 2: There should be few reasons to put the switch on BOTH (e.g. no other way to start engine). If you do put on both, remember to put it back to 1/2/ or OFF. Note 3: If you want to get a little fancier, add to Benny's solution a Blue-Sea battery combiner between battery bank #1 and #2, and connect your alternator directly to bank #1. The combiner will sense a charging voltage is present on Bank #1, and offer the power to Bank #2 simultaneously. When no charging voltage it will disconnect. Benefit, no matter your battery switch is on "1" or "2", your alternator will charge both batteries. It also helps you religiously avoid placing the switch in the BOTH position, which is bad for your batteries given the likely difference between their voltage potentials in the two banks. (also, with the alternator tied direct to bank #1, now you can move that battery switch while the engine is running) Note 4: None of these options are ideal, for getting the maximum life out of your batteries. For example, using your deep cycle to start your engine ... starter batteries are designed differently then house batteries for a reason.
I would like to add
that most switches nowdays are "connect before disconnet " type which protect delicate electronics. In effect you can go from 1 to ALL to 2 and never loose a connection. What DWC says regarding alternator charging is true as without a combiner you can only charge the selected battery. What I do is start the engine and let the alternator replenish the charge on whichever battery was used. Both my batteries are deep cycle but they barely work getting the small diesel started. I know this cuts into their longevity but after 3-4 years I'm ready to replace them anyways.
that most switches nowdays are "connect before disconnet " type which protect delicate electronics. In effect you can go from 1 to ALL to 2 and never loose a connection. What DWC says regarding alternator charging is true as without a combiner you can only charge the selected battery. What I do is start the engine and let the alternator replenish the charge on whichever battery was used. Both my batteries are deep cycle but they barely work getting the small diesel started. I know this cuts into their longevity but after 3-4 years I'm ready to replace them anyways.
Switches may be
make before break, but when, NOT if, they get old, they could not operate perfectly, and break before make. As a result, why get into a bad habit of switching at all when the alternator is running? Stu
make before break, but when, NOT if, they get old, they could not operate perfectly, and break before make. As a result, why get into a bad habit of switching at all when the alternator is running? Stu
Nick, Can You Clarify?
Do you currently (no pun intended) have one "house" bank and one starting bank (a single starting battery)? Or do you have a two-battery house bank, which you also use for starting? Or some other configuration? This info. could help bring more helpful responses.
Do you currently (no pun intended) have one "house" bank and one starting bank (a single starting battery)? Or do you have a two-battery house bank, which you also use for starting? Or some other configuration? This info. could help bring more helpful responses.
- Status