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1 battery or 2 battery Pros vs Cons by fireboss
Started on: 05-01-2014 05:27 PM
Replies: 28 (496 views)
Last post by: rogergarrison on 05-06-2014 08:31 AM
fireboss
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Report this Post05-01-2014 05:27 PM Click Here to See the Profile for firebossClick Here to Email firebossSend a Private Message to firebossEdit/Delete MessageReply w/QuoteDirect Link to This Post
I relocated my Batt. to the front and was wondering what the Pros-Cons for leaving the rear Batt hooked up...
Car is a 87 GT that I just upgraded to a CS alt,Have upgraded the stereo and added an amp.

Don't realy care about weight kept with the old batt left in the rear.
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Report this Post05-01-2014 06:12 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
Weight is the only "con" and since you're not worried about that, then you only have "pros" (although I'm not sure what they would be other than being able to play your stereo longer and louder while the engine is off).
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Report this Post05-01-2014 06:18 PM Click Here to See the Profile for trotterlgClick Here to Email trotterlgSend a Private Message to trotterlgEdit/Delete MessageReply w/QuoteDirect Link to This Post
I would say you added a battery to the front. Why would you do that? Larry
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Report this Post05-01-2014 06:25 PM Click Here to See the Profile for firebossClick Here to Email firebossSend a Private Message to firebossEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Bloozberry:

(although I'm not sure what they would be other than being able to play your stereo longer and louder while the engine is off).


We go camping alot and like to listen to the radio,and also run small things off a inverter.
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fireboss
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Report this Post05-01-2014 06:28 PM Click Here to See the Profile for firebossClick Here to Email firebossSend a Private Message to firebossEdit/Delete MessageReply w/QuoteDirect Link to This Post

fireboss

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quote
Originally posted by trotterlg:

I would say you added a battery to the front. Why would you do that? Larry


Yep had an extra Archie front batt box,And besides all the other (cool) kids were doing it....

Actually wasn't sure if 2 Batts were bad for my charging systems
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Report this Post05-01-2014 07:10 PM Click Here to See the Profile for msrservicesClick Here to visit msrservices's HomePageSend a Private Message to msrservicesEdit/Delete MessageReply w/QuoteDirect Link to This Post
Just curious, are you using any kind of circuit to isolate the batteries. So if a battery goes bad, it doesn't suck the power from the other?

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tebailey
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Report this Post05-01-2014 07:23 PM Click Here to See the Profile for tebaileyClick Here to Email tebaileySend a Private Message to tebaileyEdit/Delete MessageReply w/QuoteDirect Link to This Post
I would advise putting in a battery isolater if your using the second battery to run an inverter. That way your charging system will charge it while your running, but you won't kill your starting battery when your not. Nothing worse than packing up camp and finding out your battery is dead. Any camping supply store should be able to hook you up with one.
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fireboss
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Report this Post05-01-2014 07:47 PM Click Here to See the Profile for firebossClick Here to Email firebossSend a Private Message to firebossEdit/Delete MessageReply w/QuoteDirect Link to This Post
I haven't had both batts hooked up together yet,but if an isolator is something needed any recommendations?
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Report this Post05-01-2014 08:48 PM Click Here to See the Profile for sco77Click Here to Email sco77Send a Private Message to sco77Edit/Delete MessageReply w/QuoteDirect Link to This Post
I don't think you could ever reasonable upgrade a Fiero stereo to the point a second battery is needed (without being ridiculous).. There would be no pros to having a second battery unless you frequently use an inverter with the car off (e.g: camping). Cons would be weight, battery probably wont last as long, probably alternator as well.

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Report this Post05-01-2014 08:52 PM Click Here to See the Profile for tebaileyClick Here to Email tebaileySend a Private Message to tebaileyEdit/Delete MessageReply w/QuoteDirect Link to This Post
If you check with a camper supply shop they should be able to fix you up with what you need. It's what they use for campers and trailer so when your driving your vehicle will charge it, but it won't let you drain your main battery if you draw it down.
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Report this Post05-02-2014 03:14 AM Click Here to See the Profile for PonnariSend a Private Message to PonnariEdit/Delete MessageReply w/QuoteDirect Link to This Post
Battery Isolater is the only way to go!!!! Otherwise you will have all sorts of problems, I.e. Burned up batts, alts, etc. I've installed isolators on cars, trucks, boats, vans, and yes fieros. Make sure you get a good one, don't cheap out. RV dealers, auto parts stores, trailer supply stores. You can prob. find online too once you figure out what one you want. Good luck with your project!
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Report this Post05-02-2014 11:11 AM Click Here to See the Profile for SourmugSend a Private Message to SourmugEdit/Delete MessageReply w/QuoteDirect Link to This Post
Fierosound has two batteries, mostly for his stereo I believe. Have a look at his site and click on the wiring diagram: http://www.fierosound.com/stereo.html

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Report this Post05-02-2014 12:15 PM Click Here to See the Profile for 84fiero123Click Here to Email 84fiero123Send a Private Message to 84fiero123Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Sourmug:

Fierosound has two batteries, mostly for his stereo I believe. Have a look at his site and click on the wiring diagram: http://www.fierosound.com/stereo.html

Nolan


doesn't really matter why he has 2 batteries if they do not have some type of isolator in the system there can be problems, GM when they first did the V8 diesels in cars did the 2 battery system and had a unusual setup, I forget just what it did but think it had something to do with the amount of juice needed to turn the starter at startup and also if you didn't have some sort of isolation system in they could overcharge and drain both batteries at the same time.

look into that someone, my memory is shot.

edit to add

sorry this is from another forum but does give some good info on the duel battery set up for diesels and the mechanics, well electrics in this case are quite similar in that they are using the 2 battery system.

http://www.mastercraft.com/...howthread.php?t=3557

Steve

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[This message has been edited by 84fiero123 (edited 05-02-2014).]

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rogergarrison
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Report this Post05-02-2014 12:41 PM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
Go to an RV store and buy a battery isolator (pretty much just a Ford style solenoid) and connect it to the battery your going to use camping. It will let the alternator charge both batteries, but let you run that battery clear dead without using any power from the vehicle battery. With it, you dont have to do anything, its all automatic and you wont be stranded with 2 dead batteries.
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fireboss
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Report this Post05-02-2014 06:45 PM Click Here to See the Profile for firebossClick Here to Email firebossSend a Private Message to firebossEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanxs guys ,

Gonna get an isolator for my set up,will Isolate the front for my radio,amp,and inverter.Will put the radio on an isolated remote to run with the inginition off...
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sardonyx247
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Report this Post05-03-2014 05:00 AM Click Here to See the Profile for sardonyx247Click Here to visit sardonyx247's HomePageClick Here to Email sardonyx247Send a Private Message to sardonyx247Edit/Delete MessageReply w/QuoteDirect Link to This Post
To explain what it is, a battery isolator is just two high amp diodes(only pass voltage one way) in a big heat sink.
it has 3 posts, you hook the Alt to the center and each battery to each side. So it will charge both batteries at the same time but they can't draw from each other.
No ground needed.
When you get one, just make sure it is high enough amps to support your alternator. (They are rated in Amps)
Other wise very common for dual batteries.

On another note alot of diesels run 24volts, they do the weird circuts for the radio and stuff like that, just FYI
Totaly different than what we have to deal with.


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rogergarrison
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Report this Post05-03-2014 02:55 PM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
Heres the one hooked up to 3 batteries on my motorhome under the power panel. You can see its pretty much a pre 80s Ford starter solenoid. Prob find one in a junkyard, usually mounted on the fenderwell.



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sardonyx247
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Report this Post05-03-2014 04:38 PM Click Here to See the Profile for sardonyx247Click Here to visit sardonyx247's HomePageClick Here to Email sardonyx247Send a Private Message to sardonyx247Edit/Delete MessageReply w/QuoteDirect Link to This Post
That is not even close to all the ones I have seen, The ones I see all the time look like a big heatsink with 3 posts on top.

Edit to add, The ones I see look like this.

[This message has been edited by sardonyx247 (edited 05-03-2014).]

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Marvin McInnis
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Report this Post05-04-2014 10:58 AM Click Here to See the Profile for Marvin McInnisClick Here to visit Marvin McInnis's HomePageSend a Private Message to Marvin McInnisEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by sardonyx247:

That is not even close to all the ones I have seen,



The one in Roger's RV probably just parallels the two battery buses when the engine is running. Not the best engineering, but cheap and simple.

Another source for battery isolators is marine supply houses ... e.g. West Marine. Many large boats employ multiple battery banks.
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Report this Post05-04-2014 01:07 PM Click Here to See the Profile for msrservicesClick Here to visit msrservices's HomePageSend a Private Message to msrservicesEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by sardonyx247:

That is not even close to all the ones I have seen, The ones I see all the time look like a big heatsink with 3 posts on top.

Edit to add, The ones I see look like this.




This is like what I've seen. I had bought one to put in a truck, but never actually installed it.
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rogergarrison
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Report this Post05-04-2014 07:05 PM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes very simple, but works perfectly. You just disconnect the battery + cable from the battery and install an end to connect that to one side of the solenoid. Then you make up a new cable to go from the battery post to the other side of the solenoid. Then all you need to do is connect the items you want to run from that aux battery directly to that batterys post. A wire from the ignition hot goes to the small terminal on the solenoid. When you turn on the key, it energizes the solenoid and connects the 2 side posts together so that they are charged by the alternator. When you turn off the key, it disconnects those two posts, isolatiing the power from the aux battery from the vehicle battery. It works the same was as it does for the starter motor in a Ford. When you turn on the key, it sends the battery power to the starter motor. Mine just happens to have 2 small posts...one from the vehicle ignition to charge the aux batteries from the alternator, and the other charges the batteries from the charger/inverter when its plugged into a land line. When its unplugged and the motorhome is not running, all the 12 volt power is only taken from the aux batteries to run the coach circuits. None of the vehicle 12 volts will run off the aux batteries. ie/ the running lights and radio will drain the vehicle battery. The term 'isolator' simply means the vehicle and the coach 12 volt systems are completely seperated from each other except when charging with the ignition on.

The pictured setup is what I installed on coaches at Farber RV Manufacturing and the same as the factory installed one shown on my motorhome.
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Report this Post05-04-2014 07:13 PM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by sardonyx247:

That is not even close to all the ones I have seen, The ones I see all the time look like a big heatsink with 3 posts on top.

Edit to add, The ones I see look like this.




This is the same thing in a fancier package. Battery in, battery out and ignition hot. (3 wires). The heat sink isnt a bad idea, but not a necessity since RV builders dont necessarily use them.

There is another device that connects to battery negative post and a ground. Most places call it a battery saver. What it does is if you just have one battery, its connected inline on the ground cable, and when voltage drops to around 11 volts, it disconnects the battery from system so your battery wont go dead. If you leave say your lights or radio on and it disconnects, you just open the hood and press the reset button and you can start normally.

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Report this Post05-05-2014 07:14 AM Click Here to See the Profile for sardonyx247Click Here to visit sardonyx247's HomePageClick Here to Email sardonyx247Send a Private Message to sardonyx247Edit/Delete MessageReply w/QuoteDirect Link to This Post
The seloniod sounds like it be a bad idea, as a dead battery would draw from the other battery when it is running. The diode type prevents this altogether.
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Will
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Report this Post05-05-2014 07:41 AM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by rogergarrison:

This is the same thing in a fancier package. Battery in, battery out and ignition hot. (3 wires). The heat sink isnt a bad idea, but not a necessity since RV builders dont necessarily use them.



The device you show is a solenoid. The device with the heat sinks is a solid state relay. The solid state relay develops a lot more heat and is less efficient than the solenoid (hence the heat sink), BUT has zero moving parts to fail.

[This message has been edited by Will (edited 05-05-2014).]

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rogergarrison
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Report this Post05-05-2014 02:02 PM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by sardonyx247:

The seloniod sounds like it be a bad idea, as a dead battery would draw from the other battery when it is running. The diode type prevents this altogether.


Tell that to the RV and Boat manufacturers who have millions of them out there in use. The RV and marine industries have been using the solenoid for 40 years. I installed them as a tech at a RV manufacturer building them from the frame rails up. It only draws from the auxilary battery AND the vehicle battery when the key is on. If the key is off there is NO connection to the other battery. You can run the aux battery clear dead without taking ANY power out of the vehicle battery. I routinely use my battery power till it till all 3 aux batteries are dead on weekend trips running tvs, lights, water pump, etc. When you start it, the solenoid closes and allows the alternator to charge both. Above stated correctly with the solenoid there are no parts to wear or burn out which is why they are used. The ONLY thing that go wrong with one is the 1/2" wide brass/copper contact points inside could burn and not make contact (extrememly rare).

[This message has been edited by rogergarrison (edited 05-05-2014).]

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Will
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Report this Post05-05-2014 07:33 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by sardonyx247:

The seloniod sounds like it be a bad idea, as a dead battery would draw from the other battery when it is running. The diode type prevents this altogether.


The batteries are only connected when the alternator is energized... and charging both batteries.
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sardonyx247
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Report this Post05-06-2014 03:20 AM Click Here to See the Profile for sardonyx247Click Here to visit sardonyx247's HomePageClick Here to Email sardonyx247Send a Private Message to sardonyx247Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by rogergarrison:


Tell that to the RV and Boat manufacturers who have millions of them out there in use. The RV and marine industries have been using the solenoid for 40 years. I installed them as a tech at a RV manufacturer building them from the frame rails up. It only draws from the auxilary battery AND the vehicle battery when the key is on. If the key is off there is NO connection to the other battery. You can run the aux battery clear dead without taking ANY power out of the vehicle battery. I routinely use my battery power till it till all 3 aux batteries are dead on weekend trips running tvs, lights, water pump, etc. When you start it, the solenoid closes and allows the alternator to charge both. Above stated correctly with the solenoid there are no parts to wear or burn out which is why they are used. The ONLY thing that go wrong with one is the 1/2" wide brass/copper contact points inside could burn and not make contact (extrememly rare).



Not trying to argue, Just a good debate.
I said only when it is running, or key on, a low battery will draw from form the good battery, or if it is so dead that the alternator can't keep up with the charging demands.
or just the key on and not running. It is a design that works, The diode type I think is a better design. I say that as I have problems in the past from a bad battery draining a good one, no isolators mind you. I can completely see how the other way works, I have only used the diode type.

BTW as posted above he ment the diode has no moving parts to fail. IE: NO moving parts to fail or degrade
Just because something is 40 years old doesn't make it the best now.
All in good debate
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Will
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Report this Post05-06-2014 07:51 AM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yeah, solenoid definitely has moving parts.

Revisiting... A solid state relay shouldn't need a heat sink as it's operated in the saturated state, BUT a high power diode will need a heat sink as its waste heat is the forward bias voltage * current.
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Report this Post05-06-2014 08:31 AM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
Ill give you solenoid has one moving part...the contact point. Either one of these does the same function. I prefer the foolproof, tried and tested that also is 1/4 of the price (or free). Its simply a matter of your choice. Like I said in the industry the solenoid is the preferred one in most cases. I dont trust the newer one simply because there not as reliable long term. I have replaced them with solenoids a few times when they quit working. My travel trailer a number of years ago had the fancy new one and it quit working within 2 years. Ive seen the newer one mess up and burn out an inverter/charger to the tune of usually around $500. In all the installs and repair jobs, I dont recall ever having to replace the solenoid style one. Mine is 15 years old. Before someone thought up to use a solenoid, they used to just have a 'blade' switch. When you parked you just flipped it to disconnect it from the vehicle power. If you didnt remember to connect it back when leaving, the alternator or generator didnt charge them back up.

Again, you could just use a battery saver that costs about $50. It just connects to the battery cable and shuts off when voltage in that battery gets below 11 V. That will usually run lights and radio, etc for a while and still have enough to start after pushing the reset button. I put those in quite a few vans that dont have aux batteries. Its even good in a regular car for when you accidently leave something like the lights on. You never get caught with a dead battery. Some newer ones you dont even have to open the hood to press the reset...turning the key on activates it automaticly. Heres one brand..

http://www.prioritystart.com/

[This message has been edited by rogergarrison (edited 05-06-2014).]

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