bph
Wyoming
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Joined: 04/23/2006
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We put the 6 volts back in and the inverter started charging right away. All things function as they did before. We are off this weekend and just didn't want issues so decided to try reinstalling the old ones to see what happens. Not sure what was causing the issues other than the capacity with the 12 volts. The connections were checked by two others and they were fine. This is a puzzles still as all wires were connected and the diagram was used. The rv tech had no idea what to think other than the motor was cold. Not sure what that would have to do with the coach electrical system. But coach is kept in a heated building.
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bigfootford
Fair Oaks, California
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bph, have a safe trip, glad you got back to your operational point without major problems......
I wouldn't have very much confidence in the RV tech you were using...There isn't much science in hooking up batteries and resolving connection issues.
Jim
94 F-250 ex cab,460, E40D tranny,airbags w/pump,bilstein shocks, 2000 Bigfoot 9.6 2500 camper, Xantrex XADC 60 converter, 1 Universal group 30 AGM and an eu2000i honda genny.
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CJW8
Arizona
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Joined: 10/18/2007
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I have a friend that switched from 4-6V to 3-12 volt. He did it himself. Started having trouble right away and didn't know what the problem was. He had another friend/relative look at it and he said it looked ok. They called me over to take a look because they know I am an industrial instrument technician. At first, I said it looks ok but you had to look at it because all the 12's were not lined up with all the nag's on one side and all the pos on the other side. Two were side by side and one was on the end. Then something caught my eye and I said wait a minute. I measured the in and out post and there was only 8 volts and each battery individually was at 12+ volts. It was obvious something was not right. With three guys standing there telling me it was right I had to say no, it was not right. I got a pen and paper and drew it out for them b4 they could see it. We had to add one more battery connection (jumper) to make it right. I don't remember the circuit now but my point is, it can look right and not be right especially if the batteries are not all lined up. On his moter home things seemed to work when his engine was running because the alternator was providing 14 volts. I am guessing paralleling that with 8 volts gave him 11 volts, enough to make it work but not very good and he too had some strange symptoms.
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smkettner
Southern California
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Post a picture might solve a wire issue.
Measure the actual battery terminal voltage on each and make sure they are the same.
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bph
Wyoming
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CJW8. My husband says that makes sense. He had it wired positive to positive and then to coach. He stared at the furthest battery and doubled up the wire on the last post. Done the same way on the negative. For a total of 4 jumpers. From what we understand the alternator on our coach has nothing to do with the batteries. First one we had like that.
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Hurricaner
Hurricane Utah
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Joined: 02/17/2007
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CJW8, being a former instrument tech myself I hate to say this but come on now, how can you hook three 12 volt batteries up and get 8 volts? The answer is, you can't. My best guess is one of the 12 volt batteries is shot...have them all tested.
Sam
Sam & Kari
Hurricane, Utah
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bigfootford
Fair Oaks, California
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Sam is correct....You can't get 8 volts unless your batteries are shot when they are hooked the right way.
12 in series = 12 one battery, 24=2 batteries, 36=3 batteries, in no way can you get 8 volts!! You would fry every 12 volt item in your rig by obtaining the 24 volt or 36 volt configuration.
2 12s hooked backwards = instant arcing and welding if the batteries are in even fair shape.
You need someone to resolve this issue that knows what they are doing or someone may get hurt or you may burn your rig down.
Jim
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CJW8
Arizona
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Guys,
I didn't trouble shoot the 8 volts, I just knew there was something wrong.
Jim said "You need someone to resolve this issue that knows what they are doing or someone may get hurt or you may burn your rig down."
I did resolve it by hooking it up correctly. I know what I am doing. I routinely work on battery banks that would make a one ton truck squat! It was connected this way by someone else several days prior to my looking at it. There was no heat, fried cables, bulging batteries or arcing and sparking when I disconnected it.
Sam, you said "CJW8, being a former instrument tech myself I hate to say this but come on now, how can you hook three 12 volt batteries up and get 8 volts? The answer is, you can't. My best guess is one of the 12 volt batteries is shot...have them all tested." I agree, but like I said I didn't troubleshoot the 8 volts. I didn't care. I just knew something was wrong and I corrected it so we could get to the task at hand... riding in the dunes. Since you were a tech, you know how anal we can be about some things. I have my personal Fluke 789 calibrated annually! I know and trust the voltages I saw and knew something was wrong. It could be the batteries were down and under load when I saw the 8 volts. There were several people in the coach at the time. I have seen literally hundreds of batteries measure 12 volts until a load was applied and then read anything from 2 to 12 volts.
I never said you could wire 3 12 volt batteries to make 8 volts. I am an Instrument lead on 400 million dollar Oil and Gas platform so I think that qualifies me to know something about DC theory. You missed my whole point about some people not being able to see something was obviously wrong. I do understand and appreciate your safety concerns because I understand the current potential of large battery banks. All of those millions of little joules just stored up and waiting to get out, only held back by wire size and insulation. Given a large enough conductor, they can come all at once. Or worse, as with a reverse battery in the circuit, they collide with a big bang. If that were the case here, I think it would have happened when the batteries were first connected not several days after.
I just know the batteries were reconnected correctly and the guy dry camped several more days running lights and heat at night and recharging during the daytime had no problems with battery life.
Safety is #1 concern, then comes fun.
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bigfootford
Fair Oaks, California
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bph wrote: The rv tech had no idea what to think other than the motor was cold. Not sure what that would have to do with the coach electrical system. But coach is kept in a heated building.
I guess the above quote got my attention, among others.
We read quite often on this forum that someone will hook things up backwards or miss wire things.
Glad you can resolve this yourself and have an understanding of this type of issue.
Sorry If I offended you....
Jim
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CJW8
Arizona
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Not a problem. In my original post I was just trying to get bph to study his connections, or as smkettner replied, get him to post a picture. I hope he got it resolved. No offence taken.
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