Need help on wiring inverter and charger to 4 six volt batteries
I have a new bank of Trojans, T-105. I have 4 six volt batteries, I picked them up in Florida for $100 bucks apiece. I am hooking up a 40amp charger plus a 3000 watt inverter, all hard wired. This bank will be just for microwave and tv. I have a residential refrigerator and a separate bank of batteries for the refrigerator. On some of the wiring to the batteries I will not be able to hook all the cables to the right post. Would it be okay to bolt some of the cables together. I could drill a hole in a cable end and bolt them together right at the post. Would it be worth it to install a inline fuse on the positive side? On the inverter I have 2 positive cables and 2 negative cables. I have did this before about eight years ago but the batteries were brought from Sam's and I had more post to work with. Any help would be appreciated
If you never charge them in parallel, you are fine, otherwise you have to find a way for the negative cables to be the same length to both sets of 6V batteries. Right now if you put the negative on one, the other will have an additional 2 feet of cable and that will prevent it from sharing the charge perfectly with the other bank.
Way too many switches for my taste. You don't need to switch both the negatives and the positives, the positives would be fine. You can put a catastrophic fuse in the singe negative return. I would also invest in a roll of red electrical tape so that there is no question if a feed is positive or negative...
Unless I am missing something, you are complicating it for yourself. Read this FAQ (ZRD FAQ - Schematics) on how to wire up a battery bank. One of the pics is here. Once I get my TT, I'll post pics of my install. I will be able to be total off-grid capable when desired/needed.
The following pic shows Q6 of 6vdc batteries in series/parallel wiring allowing 12Vdc use and charging.
The two load wires are on two negative posts and the long wire on the right is connecting two positive posts together.
To make 12 volts out of two six volt batteries is to first wire positive to negative to make 12 volts then to join the four together you hook positive to positive and negative to negative
Unless I am missing something, you are complicating it for yourself. Read this FAQ (ZRD FAQ - Schematics) on how to wire up a battery bank. One of the pics is here. Once I get my TT, I'll post pics of my install. I will be able to be total off-grid capable when desired/needed.
The following pic shows Q6 of 6vdc batteries in series/parallel wiring allowing 12Vdc use and charging.
I have my battery bank wired the same way, one of my cables just has the wrong color on the end
To make 12 volts out of two six volt batteries is to first wire positive to negative to make 12 volts then to join the four together you hook positive to positive and negative to negative
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Yup.
Look at the photo of how the wires are being run.
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Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
I looked and mine are wired the same, one just happens to have a red end on it that's hooked up to the negative side
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It looks like both load wires (the red end one and the black end one above it) are on negative terminals and the long wire is between to positive terminals that go nowhere.
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Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
The batteries are hooked up right, if they were not hooked up correct then sparks would have flew. What I want to know is would it be okay to bolt the two cables that come off the inverter together. I will not have enough room on the battery post for four leads. I can also charge the new bank of batteries with the converter on the camper but I prefer not to do that. My charger is 40amps and I think that will be enough. I am going to install a 70amp converter in the camper.
Of course the question is which are the positive and which are the negative. On the left you have a separate line going to each negative and the two positives hooked together. The red shrink on the left is confusing virtually everybody...that's why a little red tape would make the whole thing better.
Yes, you can hook the negatives together at the batteries, at the switch or at the inverter or charger. Doesn't matter. In you other installation, the negatives are hooked together on one of the posts and the wire from there goes to the chassis.
Forget the switches on the negatives, put your negative lead on one of the negative posts on the left and run a wire to the other negative post. This does, however,mean that the battery with the negative on its post will get a little more loading, but since you are not using them together that should be ok. However, when you charge them there will be one slightly "loafing" battery...the one that gets a little less loading. Using your method of running separate positives to each pair, there is no way to fix that. Normally when the two pairs are connected together, you put the positive line on one pair and the negative on the other. That way the cable length is the same.
Really best to have red cables to positive and black cables for negative. With all one color chance for an error is great. Tape helps but is not as good as red cables
I am thinking that on my inverter with the two positive cables I could hook both up to one battery disconnects and then run one cable to the batteries and do the same for the negative side. The negative side is not the problem.
Really best to have red cables to positive and black cables for negative. With all one color chance for an error is great. Tape helps but is not as good as red cables
Tough to do this UNLESS you have a red on one end and a black on the other. In his pics, he has the top two in series and the bottom two in series, and then each of these pairs are in parallel.
UPDATE: Actually on second view, he DOES have a cable with red on one end and black on the other. He should be using these to hook each pair POS to NEG. Then a red-red pair and a black-black pair to parallel the two sets.
BUT: If he's going to use one of those 1/2/both/none battery switches, it will get even more complicated, as he'll need to wire each series pair to the switch separately.
make sure you have fire insurance. looks to me like undersized wiring on the batteries. bad practice to use parallel feeder wires and switches. a failed connection on one is a fire on the other.
I wish I had not took the pictures of the batteries. That was not what I was asking about. I have been hooking up batteries for ten years or more. Just forget the batteries. It was really the inverter because of the two positive cables. I don't need any advice on the batteries
The marine industry is slowly changing from Red and Black to Red and Yellow for main power runs to eliminate confusion with 120Vac Black, White and Green wiring. Not good if DC Black Negative touches AC Black Positive - Ouch!
Again, after I get my TT and finish its' installation mods, I'll post. I'll be using Red and Yellow.