I have a question before I call Xantrex Monday , I have purchased a Truecharge 40a 3 bank batt charger , also I purchased 3 new batts , 1 gp 24 starting batt , 2 gp 27 deep cycle house batts . Now my question is this granted one bank off the charger is for the starting batt ........ now for the 2 dp cycles cabled together for parallel (pos to pos and neg to neg) , is it correct to wire from the charger remaining banks 1 to each house batt or , 1 to the pair ?
Chargers vs. Battery banks
- Thread starter RoadTool
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Pair=1
I think asking the manufacturer is a great idea on this. I generally figure that any battery wired specifically together to another makes them 1 big battery, but would love to know from Xantrex if that's not a good plan! Let us know. Chris
I think asking the manufacturer is a great idea on this. I generally figure that any battery wired specifically together to another makes them 1 big battery, but would love to know from Xantrex if that's not a good plan! Let us know. Chris
I have 4 group 27, 3 house 1 starter....
From the charger they are wired one to the house (3 batteries) and one to the starter. I have found that the single battery usually needs water more frequently...more juice/charge...gets warmer? I have not had any problems charging. I am not an electrician but I think that individual cables to each battery may be better. In my case I don't think I have a choice since my charger is a 2 bank and I don't feel like getting fancy riggining it differently. abe
From the charger they are wired one to the house (3 batteries) and one to the starter. I have found that the single battery usually needs water more frequently...more juice/charge...gets warmer? I have not had any problems charging. I am not an electrician but I think that individual cables to each battery may be better. In my case I don't think I have a choice since my charger is a 2 bank and I don't feel like getting fancy riggining it differently. abe
answer to your question
The 40 AMP True Charger has Isloation diode, that means even when you connect the output to both bank they still electraly isolated from each other, so you won't discharge both banks at once. The True Charger will charge the bank that needs it up to the capatity of the charger, in your case 40 to 43 AMPs. Note that you pay attention to the wire size that is in the installation manual chart. Figure 40 AMPs to each bank and the length of wire (both ways). On you house bank you can connect to either battery in the bank because electircaly speaking the are the same. I would recommend that you get the tempature sencing that is an acessory and attach it to the battery that is in the warmest locker. All the batteries should have a common neg bar or post or if you have a battery monitor it will have a common neg output or maybe two (for each bank). Hope this helps. John USNret
The 40 AMP True Charger has Isloation diode, that means even when you connect the output to both bank they still electraly isolated from each other, so you won't discharge both banks at once. The True Charger will charge the bank that needs it up to the capatity of the charger, in your case 40 to 43 AMPs. Note that you pay attention to the wire size that is in the installation manual chart. Figure 40 AMPs to each bank and the length of wire (both ways). On you house bank you can connect to either battery in the bank because electircaly speaking the are the same. I would recommend that you get the tempature sencing that is an acessory and attach it to the battery that is in the warmest locker. All the batteries should have a common neg bar or post or if you have a battery monitor it will have a common neg output or maybe two (for each bank). Hope this helps. John USNret
Xantrex True charge
I have the Xantrex truecharge 20+. On the bottom of the charger there are three outputs that go to each battery bank. Run one wire to the starting battery, and one to the house bank. The house batteries are connected together so you should only have to run one wire to that bank. Then run the neg to a grounding bar and connect a wire to each battery bank. You should have one output left on the charger if you ever decide to install another battery bank. Just my 2¢
I have the Xantrex truecharge 20+. On the bottom of the charger there are three outputs that go to each battery bank. Run one wire to the starting battery, and one to the house bank. The house batteries are connected together so you should only have to run one wire to that bank. Then run the neg to a grounding bar and connect a wire to each battery bank. You should have one output left on the charger if you ever decide to install another battery bank. Just my 2¢
Chargers vs battery banks
Road Tool: The recent review in Practical Sailor on the Zantrex's new XC line of chargers, says that Practical Sailor fitted each bank of batteries with a temp sensor probe to avoid overcharging their batteries. While this is more importanr for a VRLA battery, it might still be a good idea for flooded type batteries. It will also allow the mixed bag charging of flooded, Gel and AGM batteries in the future if you desire to do that.
Road Tool: The recent review in Practical Sailor on the Zantrex's new XC line of chargers, says that Practical Sailor fitted each bank of batteries with a temp sensor probe to avoid overcharging their batteries. While this is more importanr for a VRLA battery, it might still be a good idea for flooded type batteries. It will also allow the mixed bag charging of flooded, Gel and AGM batteries in the future if you desire to do that.
My two cents...
Given your the capacity of your batteries, the true charge 40 is overkill in my opinion. It is designed to charge much larger banks that contain 4D and 8D batteries. Unless you're in a hurry to charge at the dock (like a cruiser ducking briefly into someone elses slip), the true charge 20 has the same features as the 20 BUT for much less money. WIth the money saved you can invest in a Xantrex's remote panel (which will act like a poor man's fuel gauge on your batteries) and their temperature sender. As for the wiring... I would wire each battery directly. That way you can shut off the battery switch when you leave the boat and know that all of your batteries are being charged. Be sure to pick the right gauge wire given the round trip distance to each battery and the ampacity of the current. Also... I would install an inline fuse in each feed wire that is no more than 150% of the maximum normal flow of amps. See the Xantrex install manual for further instruction. You can read it online on their great website... Xantrex.com I think.
Given your the capacity of your batteries, the true charge 40 is overkill in my opinion. It is designed to charge much larger banks that contain 4D and 8D batteries. Unless you're in a hurry to charge at the dock (like a cruiser ducking briefly into someone elses slip), the true charge 20 has the same features as the 20 BUT for much less money. WIth the money saved you can invest in a Xantrex's remote panel (which will act like a poor man's fuel gauge on your batteries) and their temperature sender. As for the wiring... I would wire each battery directly. That way you can shut off the battery switch when you leave the boat and know that all of your batteries are being charged. Be sure to pick the right gauge wire given the round trip distance to each battery and the ampacity of the current. Also... I would install an inline fuse in each feed wire that is no more than 150% of the maximum normal flow of amps. See the Xantrex install manual for further instruction. You can read it online on their great website... Xantrex.com I think.
One set of charger output leads per bank.
In your case leave one set of leads disconnected. The charger will direct the available necessary output to the leads of the weakest bank.
In your case leave one set of leads disconnected. The charger will direct the available necessary output to the leads of the weakest bank.
charging
April issue of Sail magazine describes the parellel configuration of 2 house batteries and 1 dedicated starting battery. they do not include a charger in the wiring diagram, but do state that the doulbe house bank is much more effective and efficient, and assure that batteries will last longer and provide reliable levels of power... you must be on the right track... Eric
April issue of Sail magazine describes the parellel configuration of 2 house batteries and 1 dedicated starting battery. they do not include a charger in the wiring diagram, but do state that the doulbe house bank is much more effective and efficient, and assure that batteries will last longer and provide reliable levels of power... you must be on the right track... Eric
Oops, the author was wrong in the SAIL article
He wrote that when using a combiner you should send the current first to the start bank and then to the house bank. Unfortunately, this is wrong, and against the instructions that come with the combiner, and makes no sense, because the house bank is usually in a lower state of charge than the start bank. As for some of the information in the posts above, I note 1. With a three output charger and two banks, only two outputs are required, since two of the individual batteries are already connected as a house "bank." makingthyme is right. 2. If you use a combiner between the house and start banks, you should use a PDP (positive distribution post) as "THE" main point of connection for the house bank and run both the alternator and (single) charger output there. The PDP "replaces" the positive post of the individual battery, since you can use it connect other things like bilge pump and stereo memory wiring, and then only have ONE wire from the PDP to the house bank. Sure, you could run these things to the positive terminal of one of the batteries (which would functionally be the same), but then you'd have four or more connections on the battery post, which is NOT good electrical practice. 3. Separate house banks will reduce the life of the batteries. Given the same daily loads, the larger the house bank the longer the batteries will last because their daily draw down is a smaller percentage of the battery capacity. The SAIL article was, again, wrong [unless only two banks were on the boat, so one was left as a backup -- having three banks makes NO sense -- a large house bank and a separate start battery are all that is required]. Sometimes the simple electrical articles written in the "popular" magazines, leave little space for getting into a subject in depth, and accordingly sometimes give incorrect information. Two or three pages are just not enough to give this subject its due. That's why so many BOOKS have been written about the subject. 4. Regardless of how you run your wiring from the charger to the banks, you should be able to turn your 1-2-B switch off when you leave the boat. The charger is wired into the incoming AC shorepower directly outputting DC to the banks. The switch should only be taking DC out of the batteries, and so should have nothing to do with charging when you're away from the boat. [In many cases the alternator output is wired to the C post on the battery switch, and the switch is thus used to both decide which bank the DC power comes OUT of, but also which bank gets charged BY the alternator. BUT, I'm guessing you're not going to be leaving your engine on when you leave the boat.]
Roadtool, looks like you've got a nice boat there. I recommend that you purchase a copy of Nigel Calder's "Boatowner's Manual for Mechanical & Electrical Systems." Rather than depending on contradictory responses on this forum, you can learn about it directly. It's important, because like everything else on a boat, it's a safety issue. BTW, they've just published a third edition, so you might be able to get a 2nd edition at a reduced price (the information you NEED hasn't changed much). Even so, it's the best $50 you'll EVER spend on your boat. Stu
He wrote that when using a combiner you should send the current first to the start bank and then to the house bank. Unfortunately, this is wrong, and against the instructions that come with the combiner, and makes no sense, because the house bank is usually in a lower state of charge than the start bank. As for some of the information in the posts above, I note 1. With a three output charger and two banks, only two outputs are required, since two of the individual batteries are already connected as a house "bank." makingthyme is right. 2. If you use a combiner between the house and start banks, you should use a PDP (positive distribution post) as "THE" main point of connection for the house bank and run both the alternator and (single) charger output there. The PDP "replaces" the positive post of the individual battery, since you can use it connect other things like bilge pump and stereo memory wiring, and then only have ONE wire from the PDP to the house bank. Sure, you could run these things to the positive terminal of one of the batteries (which would functionally be the same), but then you'd have four or more connections on the battery post, which is NOT good electrical practice. 3. Separate house banks will reduce the life of the batteries. Given the same daily loads, the larger the house bank the longer the batteries will last because their daily draw down is a smaller percentage of the battery capacity. The SAIL article was, again, wrong [unless only two banks were on the boat, so one was left as a backup -- having three banks makes NO sense -- a large house bank and a separate start battery are all that is required]. Sometimes the simple electrical articles written in the "popular" magazines, leave little space for getting into a subject in depth, and accordingly sometimes give incorrect information. Two or three pages are just not enough to give this subject its due. That's why so many BOOKS have been written about the subject. 4. Regardless of how you run your wiring from the charger to the banks, you should be able to turn your 1-2-B switch off when you leave the boat. The charger is wired into the incoming AC shorepower directly outputting DC to the banks. The switch should only be taking DC out of the batteries, and so should have nothing to do with charging when you're away from the boat. [In many cases the alternator output is wired to the C post on the battery switch, and the switch is thus used to both decide which bank the DC power comes OUT of, but also which bank gets charged BY the alternator. BUT, I'm guessing you're not going to be leaving your engine on when you leave the boat.]
Roadtool, looks like you've got a nice boat there. I recommend that you purchase a copy of Nigel Calder's "Boatowner's Manual for Mechanical & Electrical Systems." Rather than depending on contradictory responses on this forum, you can learn about it directly. It's important, because like everything else on a boat, it's a safety issue. BTW, they've just published a third edition, so you might be able to get a 2nd edition at a reduced price (the information you NEED hasn't changed much). Even so, it's the best $50 you'll EVER spend on your boat. Stu- Status