Inverter HELP please???

[Delton]

Hello Everyone!


Any and all suggestions for this scenario would be greatly appreciated:

The boat is a custom catamaran...
There are 2 motors, and each motor requires it's own starting battery. The boats (A\C)charger is currently wired to the batteries as it should be.

I'm installing an inverter (Freedom Marine 30) with a dedicated, separate battery. (Total of 3 batteries now)

How do you get the motors juice to the inverter battery for power, AND charge the 2 starting batteries in a way so that the inverter will not discharge the starting batteries?

Is there a special isolator that you can hook 2 motors up to, and have that device "sense" which of the 3 batteries needs the most juice??

What is the best way to hook this scenario up???
Any and all response will be greatly appreciated.

Thanks for any help,

Delton

[Cruisingdad]

Delton,

You can try and echo charge on the house. I have not used one because it is not how I have set up my boat... but many people use them and I believe Cam and btrayfors reccomends them.

That is all I know about them. PM Cam and he may know more.

- CD

[stevemac00]

The echo charge at 15A is insufficient to keep an inverter battery charged for that large of an inverter. You better rethink your setup.

[wildcard]

The easy way is to put in a battery isolator switch then just shut off the starting battery when not in use.

[alanl]

As a catamaran builder/sailor myself, I seriously commend putting a "house" battery between whatever energy input (generator/alternator.solar etc) and the inverter.

This will not stop you charging the house battery from the engine-driven alternator (or any other energy source) but DO install a diode into the positive line, to stop any backflow of current if the house battery voltage falls below that of the starting battery. Think of this as a one way loop with energy going into the house battery and inverter, but never the other way around. Depending on the amount of current being produced from the alternator, you may need a 30 amp diode - available from speciality industrial electronics suppliers, but probably not from consumer electronics stores. There are more expensive ways of getting the same result using a battery isolator, but the diode method is cheap and idiot-proof.

Hope this helps

Alan

[Delton]

Thank you all so much for your input. I think I have a solution and what is considered the "right way" via a device from Xantrec called a "Pathmaker".

If anyone is interested, here is the link, and there are downloadable instructions.

Thanks again!

http://www.xantrex.com/web/id/104/p/1/pt/8/product.asp

[travler37]

Leave one motor/battery separate.
do the standard house/motor bank for other.buy jumper cables long enough to do the job.Keeps them K.I.S.S.
Mark