I'm sure you guys are sick of seeing my stupid questions on here! lol

But here's another to ammuse you!

I have dual battery set up - Do I need to charge both batteries seperately or will the charge feed over from one to the other? lol

It seems stupid even to me, but I need some confirmation before I do anything! lol

(Batteries are low because of fuse to altenator, at least I think...I need to start it and see if everythings working ok now... hence the need to charge the batteries. - I tried jumpstarting it, but it didn't have enough juice. lol)

 

You can put the charger on one battery,I always put positive on one and neg on the other.One battery will charge from the other

 

You need only to connect the charger to one battery.. If you notice, there is a large battery cable connecting the two.. they are in parallel.
Note on jumping to another vehicle.. hook up the cables and start the good vehicle and "wait"... depending on how discharge the batteries are.. wait approximately 5 to 10 minutes and your truck will start OK while leaving the cables connected..
There are no stupid questions.. we are here to help each other..

 

I have to go home and try jumpstarting mine as my wife just tried cranking it and it almost caught, but the second time I got crap for rpm.......I suspect a battery issue.

If I use a battery booster type jump system....should I connect the traditional way? positive and negative to one battery?

 

I like to hook the ground to the engine away from the battery.

 

You can charge or jump from either battery. Hooking the jumper cables to the passenger battery can also give a little more umph when jumping. Less cable means less voltage drop, so more juice.

 

Posted in error....

 

Is this also the case for trickle charging through the cig lighter? The more sophisticated chargers know when to stop charging and just pulse charge as voltage drops. Does the cig lighter connection also allow both batteries to be charged simultaneously?

At one point I tried to use two Priority Start! battery minders to automatically disconnect the batteries (one on each battery) if the voltage dropped, but the wiring didn't end up being as straightforward as I imagined and the Priority start would disconnect the batteries when the truck had just started running.

Hence I lost all faith in my understating of the battery circuit.

Are the batteries in series or in parallel?

 

The two batteries are directly connected to each other in parallel..(If you connected them in series, you would have 24 volts)..

 

Don't hook up two chargers to the batteries unless you un hook them. Even though there are two batteries, they are hooked directly together. So it's more like ONE BIG battery. Anything that has power going to it is hooked up to the batteries through wiring.

By the nature of it, the batteries will always be equal. If one goes bad by itself, it will soon take the other one with it.

 

Aha so if i charge one by definition i charge the other...perhaps just more slowly then charging each separately yes?

 

I recently had an alternator failure which caused my batteries to be drained about half way down before the light came on telling me there was a problem.

While I waited for my alternator to be rebuilt I disconnected BOTH battery negative cables, and hooked up 2 small 8 amp (max) chargers, 1 to each battery, and feel that I charged them faster than just 1 charger alone would have-no harm in that IMO if you have 2 chargers available.

 

Here is great way to monitor your charging voltage..( a bit over 14 volts).. I keep it plugged into the cigarette lighter outlet all the time.. It will also indicates your glow plug relay when it is working..(voltage will be under 12 volts til the relay kicks off)

Equus Innova 3721 Battery Charging System Monitor - Walmart.com

 

Yes exactly! It's like charging one that's twice as big.

 

Why?

While I understand if you charge one, you charge the other, I see nothing wrong with using two chargers to charge both batteries while they are still connected.

Stewart