AGM House Battery Charge/Discharge

[merle&louise]

I have 6 - 8D AGM batteries connected in parallel in my coach. When I am dry camping and the Link System inside is set on amp hours when should I start the generator to recharge the batteries? The only accessories that run off of my inverter are refrigerator/freezer, TV, Aqua Hot, & lights. My basement ACs do not run off of the inverter.

Someone at POG II (I think that it was Peter vS) told me that each battery had 300 amp hours. Therefore, I assume that 1800 amp hours would be completely discharged. So would I then start the generator @ 600 amp hours of discharge if I wanted to not allow the batteries to go below 50%?

Also, what is the difference between a 4D and an 8D battery?

[jack14r]

Jon,Liberty has seen the light,their newest coaches just off the production line now have 2-4000 watt inverters.They still have otr bus air,but you can now run 2 ac units off the inverters.My 2001 Marathon has the same setup and it works great.the people at Marathon always question me when I talk about bus air,they basically stopped putting in bus air years before mine was built.They were so unfamilar with bus air they failed to reinstall the fan rheostat in their dash,wired it to the wrong batteries,and installed a 12 volt relay where a 24 volt should have been.I am the 3rd owner and the others must have run the generator as they traveled in order to run the ac.I got help from prevost on the rheostat wiring,and marathon warrantied all of the rest.It now works great.Does anyone know what type batteries(gel-agm) Marathon would have installed in 2001?

[Jon Wehrenberg]

Jack,

I try to keep life simple. If the engine is running I use the bus OTR AC to keep me cool. If the engine is shut down I am either plugged in or I am running the generator with cruise airs running.

I can't ever envision the need to run AC units off the batteries.

That's why America is great. Everybody can do it their own way.

[Jon Wehrenberg]

BTW,

Absent in these discussions is how Thompson Coach has designed and set up their coach electrical systems. I will not go into detail, but I am extremely impressed with the logic (as in both computer logic and the designer's logic) that has been applied.

The coach to start with is totally automatic. To bring it alive you use a control unit and turn two "boxes" from red to green. From that point on, your environmental settings are maintained and based on a complex set of parameters that are built into the computer logic the electrical system is monitored and the generator starts and stops as necessary to maintain a battery charge based on a large number of factors that have been programmed into the system. The coach has more inverter power than you can get in any campground so it can function as required without any input on the owner's part.

It sheds loads as required, and generally is probably better than any system I have ever read about or seen. So far it is the only coach that I know of that asks nothing of the owner in respect to systems operation because once you bring it alive, it does not matter if you are driving, dry camping or plugged into shore power. It totally manages all systems with no intervention.

[truk4u]

Hey grumpy ole man, if Tuga has 6 8d's in parallel, he has a wopping 12V at the end does he not?

[jack14r]

does anyone know what the voltages should be set at for gel cell batteries?

[merle&louise]

Are you sure that your AC is not running on AC? You would have to have pretty hefty cables from the batteries to the compressor to deliver the at least 5KW of power.[/QUOTE]

imre,

I don't understand your question. My air conditioners are running on AC from shore power or generator! The air conditioners will NOT run on the inverter.

How can I check to see if my house system is 12V or 24 V? Could I test voltage at a light socket for example? Sorry, I don't understand too much about electrical systems. That's why I like this forum, guys like you can help guys like me understand the systems in the coach.

I'm learning all the time.

[garyde]

Hi Tuga. Check your dash for Voltmeter reading guages. Do they show 12volt or 24 volt guages. That is one indicator. Also, on my Liberty , I have both 12 volt and 24 volt systems. So, you may have both as well on your Newell. The engine batteries may be 12 volt and the Coach batteries may be 24 volt . Or , like mine a combination .

[merle&louise]

Gary,

I have a 12 volt system. All of my batteries are wired in parallel, not in series.

Thanks for the help.

[Jon Wehrenberg]

IMRE,

Before you criticize Thompson, you need to understand how they are set up. Specifically they have two alternators and for the technical details you need to understand how they are hooked up.