Wiring Question - Accessories Switch?

[SSCana]

2006 Doral Thundercraft 190, Volvo Penta 3L.

So i wired in a deep cycle battery and installed an SI-ACR to isolate the cranking side. Seems to be working fine. Under the helm I wired in a junction box connected to the deep cycle through the switch/ACR that now runs the GPS. Now I want to wire the 'Accessory' switch through that box. I THINK the switch only controls the stereo. Few questions for the pros... I am most definitely not a pro:

I'll check with the volt meter but I assume the single wire that is currently going through the switch is just a positive feed? If so my plan is to remove the hot side and tape it. Then add a short feed from the junction box to the switch. Is this correct? Everything else should already be grounded.

In everyone's experience, would that switch control anything other than true accessories? I can't seem to trace the wires to anything critical.

Thanks so much. I get tons of info from this forum and just joined to get help on this little project, hoping to contribute something back some time too!

Steve

 

[Silvertip]

You presented a number a very vague terminologies that need some clarification so let's be a little more specific.
1) What sort of junction box are you referencing. Make and model or a picture would be good. Fuse panel perhaps?? You need to protect the circuit from the house battery to the junction box (fuse panel) with a fuse or circuit breaker. You also need to protect each circuit fed FROM the junction box with a fuse (which would be the case if your junction box is indeed a fuse panel).
2) Your assumption that the current wire to the ACC switch is a positive feed is correct. But that feed is from the starting battery and yes -- you can disconnect and properly insulate the end.
3) Yes -- you can add a feed from the junction box.
4) What do you mean, "everything else should be grounded?" Any device (accessory) you control with the this switch must have a ground path to the "House" battery. This would be a correct statement only if the NEGATIVE terminals of both batteries are connected together.
5) Your question "does that switch control anything other than true accessories" is rather vague. What do you consider "true accessories". ANYTHING connected to that switch is considered an accessory -- or more correctly is considered "a load."
6) You then add that you can't seem to trace the wires to anything critical. See #5. Depending on what the previous owner did or didn't do, you need to determine what items are controlled by this switch. Don't you want to know everything that switch ultimately controls?

 

[SSCana]

Like I said - definitely not a pro here, but I think I can clarify. The ACR is the Blue Sea Add-a-Battery kit, wired as per their instructions. The boat is all 'stock' from what I can tell, the previous owner didn't modify. (This forum will likely hear from the next owner of this boat as I've made a few mods!

1. The junction box I put in at the helm is a Blue Sea fuse panel. It's wired from the house side of the battery switch, I guess I need to add a breaker or fuse in that circuit, between the house battery and the fuse panel. Right now the GPS is on it, it has an in-line fuse as well as the 3 amp on the panel so well protected. The ground on the fuse panel I put in is jumped to the original panel at the helm, from what I can tell it's grounded to the bus bar at the stern. Is that okay?

2. & 3. Thanks!

4. I have to review the ground circuit. From what I can tell both batteries are attached to the bus bar at the stern. Do the ground circuits have to be isolated as well? I'll add another ground bus for the house battery circuit if I need to.
5. I figured my question was vague - just looking for an opinion on what else could be on there. Again, I can't trace it to anything other than the stereo so I'm going to go ahead and re-wire the switch with confidence.

Thanks again for your input.