Dual batteries set-up ... help needed !

[troy]

Impulse492f,
Mate i do not wish to high jack this thread but when you said you do not have to disconnect anything when charging as long as the switch is in the off position.
By doing this would i not run a risk of damaging my electricals.
First time i have had dual batteries and when i only had the one i always would tak off one terminal for this reason.
Be excellent if you are right as the way they set up my batteries i am battling to reach one let alone take off the terminal.
Thanks
Troy

[impulse492f]

Impulse492f,
Mate i do not wish to high jack this thread but when you said you do not have to disconnect anything when charging as long as the switch is in the off position.
By doing this would i not run a risk of damaging my electricals.
First time i have had dual batteries and when i only had the one i always would tak off one terminal for this reason.
Be excellent if you are right as the way they set up my batteries i am battling to reach one let alone take off the terminal.
Thanks
Troy

I can't be sure of your setup but if your off position disconnects the batteries from each other and from your boats electrics then you don't have to disconnect. You still have to connect the charger to the battery (or the connections going to the battery).

The important thing is isolate the battery(ies) from each other and from the boats electrical devices ie radio, fishfinder etc. As I said earlier all my electrics route through a common switch panel so when they are turned off I know i have no drain on the battery (and I have checked with an amp meter).

[hooknose]

Impulse is correct !!, With the master switch in the "OFF" position the batteries are effectively isolated and it is simply a matter of putting the charger on the respective batteries to charge them. I would reccomend all boaties to have in their possession a good quality battery hydrometer and to become familiar with its use. Anyone who is regularly charging batteries that they will depend upon, ie , in a boat , should have one. They are cheap and will put you in touch with any potential problems before they cause you a drama( such as a lazy cell ).
If you are worried about your electronics being damaged by surges etc it is best to try and find out from a marine electronics technician which brands feature surge protection or if a surge protection device could be fitted to your radios/ sounder/ gps etc. A battery charger should not be a problem unless the battery it is being applied to has a problem ,ie, it is open circuited, shorted, completely discharged or has been under salt water( trashed- throw it away). If the voltage in the battery is 0 volts it may take a week of trickle charging to get it to start to come up, never try to fast charge a completely flat battery( you will probably damage the charger). If this is the case always remove it from the boat and charge it( very slowly- a couple of amps max) in the garage or somewhere similar.

Cheers !!!

[Gio]

Hey Rumy1

I just rewired my old starboat when I fitted a new donk. I followed the advice in an article in Plate Aluminium Boats of Australia book three, it was written by Marine Engineer Chris Wyeth and includes easy to follow wiring diagrams to construct a system from bits available at any good chandler. Article is on page 129, well worth a look my system is working sweetly.

Cheers Gio

[impulse492f]

I noticed on post 12 my link to the wiring diagram had an error so here it is again



And the link to the website its from http://continuouswave.com/whaler/ref...alBattery.html

[dnej]

What I would add, is to separate the electronics( House Battery) from the common terminal.
To do this use two switches,not one.In that way you can use the house battery just for the electronics,isolating the start battery,which causes all the electronoc problems.
You can still position the switch, so as it can be used for emergency starts.
You also need a simple on /off switch,on the electronics outlet.
I will see if I can draw it up sometime, and repost same.
David

[dnej]

The diagram is a bit rough, but will give you the idea.
Battery one is predominately used for starting.

Set First isolation switch to position 2, and common is going to motor.At this point, battery two, is not on line to this switch.

Battery two, runs the house,and works off position 1. (This means no spikes from the start battery.)

Ok, you have an emergency,battery one is out of commisssion.
Switch position to 2, on the isolation switch.( This comes from the other battery)
On battery 2, turn off electronics,on off switch( Does the lot)
Move isolation switch to" both".

Now you have power to the motor isolation switch,at position 1,and hence power to your motor.

You could do it either way, if you needed power to the electronics. You would set the motor isolation switch to both,and the electronics isolation switch to position 2.
And away you go
Hope this is clear enough.Works a real treat.
David
i