My battery in tub setup

[Guido]

Hi guys just want to run past you all what you think I need to do with my setup.

Currently I have just a single battery under bonnet. The previous owner ran a fairly heavy wire from the positive to an Anderson plug under the tow bar for a boat winch. The negative comes out of the anderson and is fixed to the chassis close to the tow bar. It had one of those red isolating switches along the positive under the bonnet.

I have now put a projecta dbc100 isolator in place of the red switch. I want to have a short lead running from the anderson plug to a battery in the tub. So some things need clarifying:

- Can I run a positive and negative line from the Anderson to the tub battery and will this be earthed ok?
- The instructions suggest a fuse along the line. Can someone tell me what this requires and direct me to an item with a link? Sorry I'm a bit simple with electronics!

If you think I should do something differently please let me know.

Thanks for your help.
Guido

 

[04SilverSTR]

yes this will work, is there and earth coming from the front as well?, if not just earth it to the chassis, fuses are a must, 100amp inline blade fuses are in my set up.

bryan

 

[Guido]

Yes, earth from battery in the engine bay goes to side panel as standard.

 

[robmacca]

Mate....
When dealing with low voltage (ie 12v) it doesn't take much resistance for the volts to drop to a point where u will have trouble charging your 2nd battery. Once your setup is finished, get/buy a multimeter (set on DC volts) and measure the volts between the positive of the 2 batteries. You will need a long lead to do this properly so u can reach from the front to the rear. Set you multimeter on a low setting for DC volts and see what the difference is. The smaller the amount the better. Then measure the volts by going from the "-" on the MAIN battery in the engine bay to the "+" of the AUX battery in the rear, then do the same & go between the "-" & "+" terms on the MAIN battery and see what the difference is. Anything around 1>2volts is too much and your 2nd battery won't charge properly......

Oh yeah.... These VOLT measurements should be done while the ENGINE is running and a little bit above idle to.

Mine charges around the 14 to 14.1volts, which in my opinion is still a little too low for my liking so for me to install one down the rear of the car I would have to run some heavy cable (both + & -) just to help limit any voltage drop.


or u could just buy one of these:

With these units, trying to limit voltage drop to the rear is not such as important as u simply mount this unit down the back near your 2nd battery and it basically adjusts for any voltage drop and will charge your battery at the right voltage.
There's properly other brands that can be used but hopefully u get the idea


rob

 

[petez]

Does anyone have pictures of battery in the tub and the route they ran wires? I am in process of doing this and wanted some advice......cheers