12v accessory outlet: cranking or trolling battery?

[mbgaski]

Hey guys - just got a fairly simple question here. I've got a 12v accessory outlet/cigarette lighter that I'm going to be adding to my console. My boat has two batteries in the back - one for trolling and the other for cranking. Is it typically considered a better practice to wire such an outlet to the trolling or the cranking battery?

Thanks!

 

[pootnic]

Re: 12v accessory outlet: cranking or trolling battery?

I'm going say cranking but really depends on what your going to be using the outlet for.
Charging cell phone,minimal amp draw,probably doesn't matter.
A spot light,10-15 amp draw,cranking battery or another battery by itself, if going to use it alot.
What are you fusing the outlet at?

 

[mbgaski]

Re: 12v accessory outlet: cranking or trolling battery?

I'm going say cranking but really depends on what your going to be using the outlet for.
Charging cell phone,minimal amp draw,probably doesn't matter.
A spot light,10-15 amp draw,cranking battery or another battery by itself, if going to use it alot.
What are you fusing the outlet at?

I'll likely be using a 20a fuse.

As far as usage, it'll be pretty varied. Cell phone charger for sure, but I may also run other electronics such as a small laptop (carefully transported out out in the dry box ), spot light, and/or a small radio (until I install a dedicated stereo - I'm still brainstorming about mounting options before I take the plunge on that).

Motive on this was that I plan on taking the boat out catfishing at night during this season - I plan on being anchored out mostly just waiting for bites for long periods of time, and I need a power port for some accessories.

 

[wifisher]

Re: 12v accessory outlet: cranking or trolling battery?

I put mine on the cranking battery. Main reason was that it was the easiest to mount/wire that way. For the use that you described, I don't think it would matter a whole lot. Those are all pretty small loads.

 

[gasch]

Re: 12v accessory outlet: cranking or trolling battery?

I would leave the cranking battery just for that purpose alone, and use the second battery for the accesories, lights, radio and such. That way if I run the battery dead I still have a good battery to start the engine. I might also consider installing some sort of battery isolator switch, that way I have selectability to start the engine, battery # 1 or # 2 or both it give me give me more options is all. I would not want to run both batteries flat and not have no way to start my motor it could be a lond paddle across the lake when night is falling (my motor has no pull start so I need a good battery).

 

[wifisher]

Re: 12v accessory outlet: cranking or trolling battery?

I would leave the cranking battery just for that purpose alone, and use the second battery for the accesories, lights, radio and such. That way if I run the battery dead I still have a good battery to start the engine. I might also consider installing some sort of battery isolator switch, that way I have selectability to start the engine, battery # 1 or # 2 or both it give me give me more options is all. I would not want to run both batteries flat and not have no way to start my motor it could be a lond paddle across the lake when night is falling (my motor has no pull start so I need a good battery).

A 40hp is pretty easy to pull start if the battery is dead.

 

[gasch]

Re: 12v accessory outlet: cranking or trolling battery?

your has a pull start, lucky you
mine 33hp does not.

 

[pootnic]

Re: 12v accessory outlet: cranking or trolling battery?

If your going to be anchored(cat fishing),doesn't seem like the trolling motor battery will get used to much and a pull cord for your motor.
So for you guess it doesn't matter to much which one you use.
Are both batteries deep cycle?

 

[bruceb58]

Re: 12v accessory outlet: cranking or trolling battery?

For the loads you are likely to put there, I doubt it matters.

As far as 20A fuse on that circuit, that seems kinda high. Fortunately, most loads will have a their own fuse so you are probably OK.

 

[NYBo]

Re: 12v accessory outlet: cranking or trolling battery?

As far as 20A fuse on that circuit, that seems kinda high. Fortunately, most loads will have a their own fuse so you are probably OK.

Plus, most of those accessory outlets are rated for 10A.

 

[sschefer]

Re: 12v accessory outlet: cranking or trolling battery?

Typically you would use a battery switch and just put the 12v outlet on the main circuit off the fuse box. You can then switch from main to aux battery freely or combine the two if needed. I like the Perko switches but Blue Sea makes a decent one also.