Wiring everything

swimmin' for shore

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Oct 25, 2004
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490
Okay. I'm not an electrician anymore than I'm a mechanic. It's time to learn to do this stuff, though. The boat that I'm dealing with is a 78 Sea nymph flat bottom aluminum boat that has been modified like a bass boat, with high decks, steering console at the stbd center, and drop down trolling motor at the forward end of the boat. Here's where I'm at, and what I've done. Questions to follow that:

1. The wiring, from front to back of the boat was a bird's nest. It all ran down the stbd side, under the deck. I could access it, but had to do a lot of untying and tracing to figure out what went to what. I reran every piece of wire that looked bad and put in marine grade wiring. I don't have all of the different wires to differentiate, but I got ahold of 7 or 8 different colored electrical tapes, and taped each accessory at 3 foot intervals for easy identification in the future.
2. I cleaned up the whole birdsnest back by the splashwell. It was just a big knot, and I reran or straightened out everything, and then clamped and screwed it into the transom with wire clamps so it all runs in straight lines and is up off the floor, which is obviously going to get wet sometimes. It's very neat now, and I admit to a little bit of pride, not to mention some relief to have it done.
3. I bought 2 deep cycle batteries and installed them in that aft cross-seat, beneath the deck. The interior of that is sealed to be water resistant, and has a wood bottom, but just to keep the batteries from bouncing around, I strapped them in place.
4. Under the fuse box(beneath the steering console) was the next bird nest, and I did pretty much the same thing. I traced and pulled out loose, old wires that no longer go to anything. I straighened, shortened, and clamped everything else. I can actually close the fuse box now. Amazing!

Now we come to the questions. It's been easy enough to straighten up the mess, if a little time consuming. I'm going to buy a perko 3 position switch(1-2-all) tomorrow, and I need to get this thing wired, put the outboard back on, and figure out what goes to where. I don't have any diagrams to go by, but this is how I'm understanding it. If I'm wrong, somewhere along the way, or if anyone can add any insight or anything that I miss, please fix me. I'll thank you a thousand times over.
Battery 1 positive goes to switch, position 1. Batt. 2 pos. to switch position. 2.
Switch gets a hot wire to fuse panel. Is it also wired on a separate wire to the key, which provides the power for the ignition module for the outboard?
All accessories, including bilge pump switches, bow and stern lights, cabin lights, and radio currently run to the fuse panel, which has fuses and toggle switches. I know I need to run a ground from the fuse panel. Do I ground from fuse panel to battery, and then ground from each individual accessory to that ground point on the fuse panel or can I ground accessories individually to the battery and save a whole lot of wire?
Rereading my own writing, I know how people end up with a bird nest of wiring. It's a little confusing. Please understand that I do have a basic understanding of what I'm doing here, but I don't claim to be any kind of electrician. I'm just looking, in the end, to have clean, neat, and safe wiring with 2 batteries(one providing backup power and power to the trolling motor), one switch, one fuse panel, 6 or 8 accessories, and one 35 hp Johnson Seahorse. And if it takes me until spring, I will get this right. :)
 

swimmin' for shore

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Messages
490
Re: Wiring everything

I looked at that, but all it tells me is to wire the positive terminals to the switches. Am I right about the wiring from there: Positive from switch to fusebox and ignition and negative from fusebox to battery?
 

tashasdaddy

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51,019
Re: Wiring everything

ignition should be powered form the engine battery cables, thru the engine harness. to run the accessories, you are correct, and can put a master switch before the fuse panel that turn everything off, to cut down on battery drain.
 

bruceb58

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Re: Wiring everything

Any run from the battery, be it from the perko switch or the battery itself, needs to be fused at the battery. Exception is the large lead that goes to the starter motor.

The long feeder wire(large guage) should go through a large circuit breaker before it make the long run to your fusebox. At the fuse box, you make all your connections to assesories and the ignition switch. One option for the ignition is to have a second smaller breaker near the battery so that the ignition goes through this breaker instead of the fuse box. Just rememember that you should not run any wire from the battery unless it is fused/or breakered.

You will have an equally long ground(large guage) that also goes to where your fusebox is so that you can mount the grounds all at one point.
 

tashasdaddy

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Re: Wiring everything

bruce you are correct, on the fuse situation. but i perfer my ignition to be for the engine only, and a master for all the accessories.
 

Reel Poor

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Re: Wiring everything

By using a buss bar you can eliminate grounding all the wires directly to the battery. Mount it local to both batteries.

Groundbuss.jpg


When running dual batteries I recommend using either a battery isolator.

DualBatteriesIsolator.jpg
 

bruceb58

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Re: Wiring everything

Reel Poor,

Nice diagram. I would probably run a seperate cable straight to the starter without going to a bus bar though. I would run a seperate large guage wire to the bus bar.

Same thing applies to the ground.
 

bruceb58

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Re: Wiring everything

tashasdaddy said:
bruce you are correct, on the fuse situation. but i perfer my ignition to be for the engine only, and a master for all the accessories.

So you are saying have two breakers..one for the ignition and one for the rest of the dash/accessories?
 

Reel Poor

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Re: Wiring everything

bruceb58 said:
I would probably run a seperate cable straight to the starter without going to a bus bar though. I would run a seperate large guage wire to the bus bar.

That would be ok. Thats the way I would do it also.

bruceb58 said:
Same thing applies to the ground.

Run both battery ground wires to the engine. Then with a large wire run from the engine ground or "both" batteries to the buss bar. Wired this way either battery can be used to start the engine. This will prevent backfeeding to the engine through smaller ground wires if your cranking battery fails and you have to use you second batt to start the engine.

 

swimmin' for shore

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Messages
490
Re: Wiring everything

Okay. As I understand it then, everything runs as follows:
Positive:
Battery 1 to terminal 1 on switch
Battery 2 to terminal 2 on switch.
Common to a circuit breaker
Circuit breaker to ignition switch, fuse panel, and electric trolling motor.

Negative from both batteries to a grounding bus, and then everything grounds to this bus.

Where do I buy this circuit breaker and grounding bus? Home Depot, auto parts store, or boater's world?
 

Reel Poor

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Re: Wiring everything

If you use two fuse panels under the console you can use one to supply ignition system and all other necessary options, ie, lights, horn, navigation electronics, ect. Use the second to supply all accessories, ie, livewell pump, stereo, VHF, !2 volt supply outlets, ect. By running your trolling motor directly to battery #2, you can turn the battery switch to the off position and only be using from that battery while running the trolling motor. By switching to batt 2 you can still run all your accessories, while saving battery 1 for starting.

Note all the changes I made to the wiring diagram. The first one I posted was kind of a generic diagram. This one is more specific to your application. Its not necessary to use two fuse boxes, 1 would do just as well. Just be sure to use large enough wire to carry the load fo multiple circuits.

DualBatteriesIsolator02.jpg


This fuse box has positive and negative terminals, so it needs a pos (from batt switch) and neg feed (from ground buss).

5026_200.jpg


Click Here For Circuit Breakers

Maxi Fuse---up to 80 amps

5006_200.jpg
 

bruceb58

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Re: Wiring everything

swimmin' said:
Circuit breaker to ignition switch, fuse panel, and electric trolling motor.

Negative from both batteries to a grounding bus, and then everything grounds to this bus.

Run grounds from your battery directly to the block. Run a seperate ground(large guage) to your fuse panel. Not sure if it is really necessary to have a ground bus near the batteries unless you have a local fuse panel back there. In your case you may want one...you get to decide if you need it.


Your trolling motor should not go through the same circuit breaker that feed your remote fuse panel. See what the trolling motor manufacturer recomends for its hookup in its manual.

Bluesea makes a lot of what you need. Many mail order places carry their items.


Edit: After I wrote all this I realize that reel poor pretty much has everything in his diagram.
 

jlinder

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1,086
Re: Wiring everything

I am probably too late for this, but it pays to give some real thought to the guage of the wire you are using. Especially the main run from the battery to the front panel.

You not only need to make sure the wire is heavy enough to safely run the amperage you are drawing now, but to minimize the voltage drop from the battery. You also want to plan for any possible expansion in the future.

Most people know to figure out the guage of wire for safety, but voltage drop is often not considered.

There are a lot of postings here on voltage drop - how to calculate it and what to keep it under. Rather than post it again just do a search for voltage drop.
 

swimmin' for shore

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Oct 25, 2004
Messages
490
Re: Wiring everything

Guys, thank you for everything you've helped with thus far.
Reel Poor, I ca n't see diagrams on this computer. I'd be eternally appreciative if someone would get my email address from my profile and send an email with the diagrams in it.
My motor isn't hooked up yet(I'm trying to complete a 30 item list at the same time), but there are 2 cables for the battery that come directly from motor, so the motor is automatically grounded to the battery(when I hook it up).
The wires that I ran from the battery(switch) to the fuse panel are marine grade 10ga. I thought it might be a little light at first, but I realized that I'm not really using much juice, beyond the fuse panel. Bilge pumps, aerator for the livewell, and lights. If I need to switch up to 8 ga., please tell me now. It's a quick switch, at this point.
The fuse panel is currently grounded directly to the batteries. All of the accessories ground to the fuse panel.
The trolling motor runs to the battery switch, so I went ahead and trusted myself not to leave the switch on "All" while trolling. I don't do much trolling anyway, so I'm not too concerned about that being a problem in the future.
I don't have a radio or any other accessories in the boat. There's a humminbird fishfinder, and that is actually rigged to a 2nd 3 block fuse panel that is run separately from the other. The only thing that's on there right now is a cigarette lighter plug-in and that fish finder. There's no stereo or CB in the boat, although I'm prepared to face those things somewhere along the line.
Only one question, from everything that I've seen here. Do I run this negative from my fuse block to the battery or do I run it to the engine, which is grounded? If I run it to the engine, where exactly am I supposed to tie into on the motor?
 
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