Dual battery set up problem

[us71na]

Originally Posted by Mustang65

Here is the most efficient method for hooking up (2) 12Volt batteries in paralllel. It produces a more even charge and discharge.

Also, go an Amazon and get an inexpensive digital voltage display that plugs into your TT's 12VDC accessory plug, so you can monitor your batterys to insure that the voltage does not drop below 12VDC. The battery monitor lights on the TT are not really worth anything.
Don

If both batteries are the same type and condition, electrically it doesn't make any difference for either charging or discharging. Both batteries see equal voltage and current and will provide equal voltage and current. There might be some advantage with batteries of differing capacity but connecting different capacity batteries in parallel is not a good idea.

[sebring96hbg]

Your usage sounds about right. You have a 150 AH battery bank and you should not discharge more than 50% or 75 AH. You watched three plus hours of TV at 20+ AH equaling 60+ AH plus the AH for the heater and other things.

[Mustang65]

Originally Posted by us71na

If both batteries are the same type and condition, electrically it doesn't make any difference for either charging or discharging. Both batteries see equal voltage and current and will provide equal voltage and current. There might be some advantage with batteries of differing capacity but connecting different capacity batteries in parallel is not a good idea.

Here are examples (comparison of different methods) to support the method of connecting the load to the Positive terminal of one battery and to the Negative terminal of the second battery in a parallel configuration. Since there are only two batteries the numbers will not be as great, but still will affect the charging/discharging of the battery bank.
Don

[Mustang65]

Originally Posted by sebring96hbg

I got this for display:

Amazon.com: INNOVA 3721 Battery and Charging System Monitor: Automotive

That should do the trick and allow you to keep an eye on the voltage of your batteries. You can double check the plug in voltage with a volt/ohm meter at the batteries.
Don

[Mustang65]

I was asked where I got the information that explains why the method that I posted is better. If you go to their homepage it gives you a little background on the company.
Don

Here is the link
http://www.smartgauge.co.uk/batt_con.html

[Jmooney]

And your inverter is pulling its own load too, so be sure to turn it off when not watching TV