isolated battery-NEED pos,neg,earth isolated too!

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  #41  
Old 05-10-16, 04:39 AM
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Strange..and i have the same picture as ref. Had to replace everything.

I`m just waiting on the part now.
call ya if it breaks...ha
 
  #42  
Old 05-16-16, 11:27 PM
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I have to ask....your diagram is a parallel set up but I have seen one that connects to a VSR (pos only) and it only mentions the neg from both battery's connect to the vehicle independently (or with the 3 lines of earthing symbol) and not get a cable connection.
Is it possible to set up the dual battery's in this way, especially with a component?. Yet it is still a parallel battery configuration?.
 
  #43  
Old 05-17-16, 12:20 AM
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Sorry, I do not understand your question. Can you post the diagram?
 
  #44  
Old 05-18-16, 09:13 AM
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do you assume its all joined then?
 
  #45  
Old 05-18-16, 10:59 AM
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The metal frame is the "wire" connecting all the negative poles together.

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  #46  
Old 05-20-16, 05:10 AM
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......so i am going to ask my final and most obvious question.....

-how do you decide where this connection to the frame occurs and when a pos - neg connection (for light bulbs) happens?

Does it matter..or I just assume that the metal frame will connect both.....IF the car is welded around the middle still !?!

P.S.
I just found out that to parallel battery's they must be of equal quantity-or the same. CCR or cranking capability.
so that`s that then. and Ive gone and bought the part-any connection between them is impossible.
 
  #47  
Old 05-20-16, 10:22 AM
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The closest place you can get a solid ground to the chassis.
I just found out that to parallel battery's they must be of equal quantity-or the same. CCR or cranking capability.
Why? It is not connected when you crank. That is why the isolater is connected to to an ignition wire that is not live when the truck cranks.

Strongly suggest you let an RV repair shop or automotive electrical repair shop install it for you.
 
  #48  
Old 05-20-16, 07:28 PM
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agreed,(lengthy thread in simplicity) the next stop is to auto elec. last guy was a battery expert.
he seemed to EXPRESS the same battery MUST be the same...so?!

yes big job, considering 2 parallel is the answer!
 
  #49  
Old 05-21-16, 12:13 AM
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Two batteries of dissimilar capacity connected in parallel will charge at different rates. Depending on the difference you can easily end up with one battery constantly being overcharged while the other battery is never fully charged. This will contribute to both batteries failing long before either normally would if charged correctly.

The same can happen even if the two batteries are of the same capacity if one of them is frequently discharged to a much greater degree than the other.

Bottom line is, batteries in parallel should be avoided whenever possible but if it cannot be avoided they should ALWAYS be used in parallel or else they should be swapped around on a regular basis so they get equal usage as well as equal time being charged.
 
  #50  
Old 05-22-16, 10:54 AM
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..that`s a lot more information than I got from the auto elec. Thanks.
He couldn't see anything about it and I should see a radio guy, that`s his advice..oh and use the frame for an earth...shrugs...

(what is the world coming to)

I even asked how much metal is needed to trick/make an earth point and that was hard..unknown. I`m sure it was a quantity
 
  #51  
Old 05-22-16, 12:00 PM
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I even asked how much metal is needed to trick/make an earth point and that was hard..unknown. I`m sure it was a quantity
You ground to the metal frame of the car whose metal then acts as a wire to the negative side of the battery. That is all you can do. The metal frame is always enough. It has far more capacity to carry current then any wire you would ever use.

Earth does not mean a connection to the planet Earth in this case. It is a connection to the metal frame of the car. Maybe that is what is confusing you.

If you're having trouble finding someone to do it go to an RV repair shop. The system you need is commonly used in RVs.
 

Last edited by ray2047; 05-22-16 at 12:18 PM.
  #52  
Old 05-22-16, 12:30 PM
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We have gone through over 50 posts and we are really no further than when we started.
It sounds to me that if you can not understand how to fix your problem by now and you make a mistake in connecting something you will be back where you started with damaged components.

I am closing this thread and encourage you to take your vehicle to a competent repair shop.
 
 

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