View Full Version : Issues with new setup...

10-20-2011, 07:45 AM
Well now that ive re-wired everything im having a weird electrical issue, so im sure it must be something in my wiring. Ive had all 3 amps in the boat before and this never happened, so unless my Alt is starting to die and act funny Im pretty sure its in the wiring.

So here is the setup, 3 amps, 2 batteries, 100amp "Battery Doctor" Isolator.

Right now I have

Starting battery - 0/1 awg positive and negative from the engine block / start to crank the boat, along with the 4awg positive and negative from the dash (power bilge, dash, lights, and ballast.

From the starting battery a positive terminal a wire runs to the "Main" connector on the Battery Doctor isolator. From "Aux" terminal on the battery doctor it goes to a 150amp breaker and then to the positive terminal on the AUX battery. The positive terminal feeds a 135amp breaker, which then feeds a distribution block, and each amp connects to that.

From the starting battery negative terminal, a wire runs to the negative terminal on the AUX battery, which then feeds the negative distribution block, and the amp negatives are fed into the distribution block.

The battery doctor also has a negative wire which is connected to the AUX batteries negative terminal

It seems that after a bit of high volume playing, the isolator goes into Charging over current mode. According to the manual this mean:

Charing-Over Current: Excessive current flowing while in charging mode. Over current can be reset by pressing the override/reset button or will automatice reset when the starting battery is below 12.8v indicating that the engine has stopped

Im not sure what is triggering this issue, im going to follow all my grounds and make sure everyhing is grounded properly, but im pretty sure it is.

I noticed this because the stereo would start to cut out at around 22 on the volume when usually it can go up to 25-27.

I took reading on both batteries, and since the isolator has stopped charging the aux battery, it was reading about 8v, while the starting battery was readying about 14 with the engine running.

Any ideas?

10-20-2011, 08:21 AM

I check the voltage of each battery with the engine off, 12 on the starting battery and 11 on the aux battery.

I cranked the engine with all amps turned off, and both batteries were reading 12.8v... so i think the alt is charging fine.

Could it be that when the AUX battery drains and starts to charge, its drawing too many amps and causing the isolator to fault. This model is 100amp (75 constant, peak 100) ... they make a 150amp model (125constant, 150 peak)??

10-20-2011, 01:36 PM
no one has any ideas?

10-23-2011, 12:46 PM
Sounds like you're running down the aux battery too much with the stereo, not knowing exactly how the battery doctor works.
Have you pulled both batteries and charged them fully? DOes the condition happen right away like it does without shore charging them?
ANother thing, do you have one ground servicing both batteries? It's reccomended to have the same capacity of ground as pos wiring. I have 2 separae 2ga grounds, one from each battery back to the block.
Also I have a very good battery on the house (stereo) load and a charger/tender to juice them back up after a day on the lake.
Mind you, my boat/stereo get's nowhere near the use of yours.

10-24-2011, 07:58 AM
I figured out my issue.

I was over loading the battery doctor. Switch over to the stinger 200amp isolator and everything is working fine. I know im pulling between 100 (since i was overlaoding the 100amp battery doctor) and 135amps since the breaker the distribution block is on is 135amp.