Wiring From Scratch

[Rjnelson1184]

I just acquired a 16 ft Starcraft from either the late 60's or early 70's. I have torn everything out and I am in the process of fixing every hole, dent, and scratch on the entire boat. Basically I made this small fiberglass boat my first big project. I have done a lot of research on the cosmetic work but just recently started to look into the Electrical part of this project. I am starting from scratch and don't have a clue where to start. I have wired small things in my fathers boat(nav lights, bilge). I have looked up somethings on this forum like diagrams and it all seems straight to the point. But what I would like to do to this boat isn't like any diagram I have seen. The components I want to put in are the nav lights, courtesy lights, a flood light, live well, bilge, am/fm cdplayer and speakers, a vhf radio, an aux port(cigarette lighter) and of course the fishfinder. My questions are should I have 2 batteries or 1, what is the difference between a circuit breaker and a bus bar, what exactly does the bus bar do, what components could I put on one circuit or bus bar, what gauge wire should i use, and finally where should I start.

 

[Silvertip]

Re: Wiring From Scratch

I don't mean to be critical here but you need to head to your local library and do some reading on basic DC circuits -- especially if you don't know the difference between a circuit breaker and a buss bar. A circuit breaker serves the same function as a fuse. A buss bar (+12 volt and ground) are the points where +12 volt and ground connections are made. As for the wiring itself, nearly everything on the boat can be wired with 16 gauge marine wire and by all means use the proper colors. You can find the marine color code by doing a Yahoo or Google search. Look at the generic boat wiring diagram "sticky" at the top of this forum. It doesn't matter what you want to add in the form of electrical items. They are all wired basically the same way except for Nav/Anchor lights which take a special switch. Bilge pumps, blowers, lights, accessory sockets are just 12 volt electrical devices. They need a +12 volt source, a fuse to protect the circuit, a switch to turn the item on, and a ground connection. Unless you plan on a super high power stereo system or a trolling motor, you don't need a second battery. Just a good quality starting or dual purpose (starting/deep cycle) battery.

 

[Medic4040]

Re: Wiring From Scratch

When redoing the electrical in my boat i was told I am going to want to stay away from a bus bar due to the fact that it was a lot of exposed metal and just another place for a short to occur. I used a fuse block and have not had a problem with it, and am glad I did it that way because I have that extra protection for all my expensive accessories. Good luck!

 

[bruceb58]

Re: Wiring From Scratch

You can buy bus bars that have covers.

 

[Silvertip]

Re: Wiring From Scratch

Bus "bars" and "a bus" are rather nebulous terms. Most fuse panels have a ground "bus" built into them so a "ground bus bar" is not even needed.

 

[Rjnelson1184]

Re: Wiring From Scratch

Thank you for your input. I will probably now only use a good fuse panel. I am thinking of doing a lot of late night striper fishing in the back bays where I am from. If I use the lights(courtesy and nav), radios(am/fm cdplayer and vhf) and livewell for long periods of time drain one battery? I do not want to be stuck in the dark. and lastly should I put in all the electronics before I put in an outboard, or will it be easier to wait till I get an outboard put in?

 

[gcboat]

Re: Wiring From Scratch

O.K. So we're gonna' do some electrical work eh? First off do as Silvertip mentioned and get some reading done. Here's a start:http://www.amazon.com/s/?ie=UTF8&ke...=aps&hvadid=1500924341&ref=pd_sl_52hg1g5pcr_e
I would highly recommend the first one ( 12 volt bible ). Pulled me out of a few scrapes.
There are usually two things a boat just can't get enough of - one is fuel (unless you're on fire) and the other is electricity. What you need to understand is that you're just not going to be able to have everything you want - electrical wise - on that boat.
A dual battery set up is ideal with a decent MBSS ( master battery selector switch). They can be found in the boat parts and accessories section at the header of this page.
As far as motor first or whatever it really can't and usually doesn't make a big difference. The only wire (s) you'll need back there would be for your nav lights.
You really need to reevaluate your electrical wants and desires.

 

[Rjnelson1184]

Re: Wiring From Scratch

gcboat why will I not be able to get everything electrical wise on the boat? Guess I could do without a am/fm cdplayer with speakers and probably could get a hand held vhf, but if I can I would like to get everything on the boat. I mean late at night anything to help me from going crazy from boredom will be great.

 

[Big Keepers]

Re: Wiring From Scratch

Those books mentioned are great. Wiring up what you want is not going to be difficult at all, just time consuming. Keep in mind that you'll have a decent amount of wire to keep tidy especially near your fuse panel or buss bars. You'll want to figure out how you plan on running wires where you need them. Personally I'd use a two battery set up which is how my 20' MFG is wired. I used Blue Sea's "add a battery kit."

To simply describe my set up, I have a house battery for my electronics and switch panel at the helm. I used 8awg to run +12 to a buss and the same size wire to run ground back to the battery from a ground bus. The +12 is protected by a 30amp maxi fuse about 12" from the battery switch. This protects the length of wire. My switch panel taps into the positive buss as does my VHF and sonar/GPS combo. The vhf and sonar have their own fuses inline as well and are grounded to the negative buss. Each switch on my panel has its own round auto style glass fuse. These switches are for my bilge pumps, nav/anchor lights and courtesy lights. Each of these are grounded to the negative buss as well.

 

[pwfish1]

Re: Wiring From Scratch

big keepers, on your set up, is there a main switch to turn all juice to electronics?....where is the pos for all electronics?..does bus provide this or is all wired to main harness?

need to go to library!!!

thanks

 

[Rjnelson1184]

Re: Wiring From Scratch

Ok big keepers, now we are getting back to these buss bars. Obviously I need to do my reading but I would like to see many other peoples' opinions. Your buss bars, you have 2? One for the positive and one for negative? I wish I could find a more in depth diagram on these things. I only have like 6-10 electronics on my boat yet most of them will be running at all times, so I need to be aware of any possible over heating wires. Knowing all possible techniques will help me prevent a wire from getting hot. A fire could ruin a great night fishing.

 

[Big Keepers]

Get your pencils out and load up that printer with ink

Get your pencils out and load up that printer with ink

Okay here goes. I'll try as best as I can to not bore the absolute crap out of all of the readers who don't need to know this stuff.

To start with I have a deep cycle battery and a Sears Diehard starting battery in the rear of my boat on the starboard side. I used Blue Sea's Add a battery kit to hook the two batteries up. The battery has four posts but each side is independent of the other. If necessary the switch has a selection for linking both batteries for emergency starts. It came with the automatic charging relay so both batteries get charged without losing current to an isolator.

So for the house side (deep cycle battery) I ran a wire up to my helm which connects to a 10 screw bus. There is a 1/4 stud on it and then ten #8 screws which is where you connect your accessories to via small ring connectors. I have two of these under my dash, one is negative so that lead goes all the way back to the house battery negative terminal. I can't find a picture of them but they are small, about 2" wide and maybe 7" long. They can handle like 120 amps or something. This link is for the smaller ones but they have them with up to 20 #8 screws.

http://bluesea.com/category/9/35/productline/184

Wiring it this way means I only have to run two 8awg wires from my batteries to my helm. As I stated previously, within 7" of the house battery (ABYC spec) I have my 30 amp maxi fuse which protects everything down stream of the switch. I probably could have used a 20 amp fuse but I picked 30 amps.

I have a Lowrance GPS/Sonar combo and a VHF. They each came with their own fuses that had to be soldered inline with the positive leads coming off the unit to keep the warranty in place. So they hook up to my buses under the helm. My switch panel I made out of starboard and has 8 switches I believe. I piggy backed each switch to the next and at the end I have about a foot of extra wire. So my switch panel is screwed into the positive bus as well. My anchor light, nav light, bilge pumps, and small LED courtesy lights all run up to the helm. The positive wire goes to its proper switch and the negative goes to the negative bus. I used the Ancor two way wire that comes wrapped in the white plastic sheathing like household electrical wire. I ran all my electrical wires that come from the rear and the wires coming off my Yamaha down the starboard side under the gunwale and its tied up neatly with zip ties and rubber clamps that screw into a wood piece that runs along the gunwale.

All my gauges are getting power off the key switch. When I bought my Yamaha from its previous owner I took the time to disconnect all the wires under his dash so that I had them to reconnect all the gauges. I didn't just go in there with wire cutters and cut everything. He gave me everything with it, controls, gauges, etc. It is as if the factory installed my engine for me. So when I'm out fishing or hanging out with other friends. The motor is off, but I have power to my VHF and GPS. When I get around to putting a stereo in I'll have that going right off the bus too. I can turn on my courtesy lights and anchor light as well because the switch panel taps into the bus. I don't have to leave the key turned on for anything but starting the engine and running it.

It may sound like a confusing mess but in the event I have to troubleshoot something I don't have to look for which wire is tapped into this or that like some boats. I've seen people splice into gauge wires, key switch wires and stuff like that. When they have a problem with something it could be originating anywhere. If I have a problem I know where to look. If my VHF cuts out I only have to trace two wires from the bus to the unit. If I have power and ground to my buses then half the troubleshooting is over. When I get around to putting in a stereo or my cabin light or maybe something else I only have to screw two wires into the buses and I'm done in ten minutes.

The only wires connected to my battery are the positive leads to the switch and the ground leads between batteries and one lead from the negative bus and one lead from the charging relay. If I need power for something in the rear of the boat I go directly to the battery switch and use a 3/8 ring terminal (like my automatic bilge pump.) I don't like to have six different wires coming off the battery. In the winter I disconnect four wires and I'm done in ten minutes.

 

[pwfish1]

Re: Wiring From Scratch

BIG KEEPERS..beatiful explanation for us electricaly challenged...few ??...what brand/model bussbar are you using? your set up is everything i use and tryingh duplicate.

how much was the battery kit?

for now i'm using a battery that has starter and deep cycle capabilities. will get to the 2 system soon.

all your gauges getting power off key switch.

i want a seperate power switch for accessories. power lead back to pos battery term and neg to bus. do accessories get wired to pos term on switch and neg on bus??

i dont want to splice accessories into main harness with key.

this ok??

thanks

 

[Big Keepers]

Re: Wiring From Scratch

BIG KEEPERS..beatiful explanation for us electricaly challenged...few ??...what brand/model bussbar are you using? your set up is everything i use and tryingh duplicate.

I use Blue Sea buss terminals

how much was the battery kit?

I believe Blue Sea's Add a battery kit is about $150.

all your gauges getting power off key switch.

That is the way it should be. The yellow wire (usually) coming off the remote control box is the +12 wire when the key is turned on. That is where your gauges get power. Tapping into this wire for power to accessories leads to a voltage drop on your gauges and causes faulty readings on them.

i want a seperate power switch for accessories. power lead back to pos battery term and neg to bus. do accessories get wired to pos term on switch and neg on bus??

Yes, for some reason when I rigged the bow rider in my marine tech class we put toggle switches on the panel for the stereo, VHF and the GPS/Sonar combo. So the positive lead for the accessory goes to the switch and the ground goes directly to the buss. It is kind of redundant since you cut all power to the positive buss when you turn the main battery switch off.

 

[pwfish1]

Re: Wiring From Scratch

Big..i'm getting a much better picture of what;s going on from reading, and reading etc..

gauges off main harness only makes sense, those readings are coming off the motor anyway, except for gas. The diagram on the site has a wire from all gauges and accessories going to volts. is this important??

I'm sure i can use one of the bussbar that has the pos/neg term all on one panel. The bussbar is generally what is supplying the power for accessories. I'm running a pos wire to pos side of bussbar and battery. Can i take a on/off power switch and just use it for accessories??

if i can't get my rpm and mph gauges to work i can presume the wires off the motor are wrong??? I can possibly figure this out if the color wiring is correct off the motor according to boat color code. Also, i have a 60hp merc, there a few disconected wires under cowel, some are taped off.

Thanks for your help.

paul

 

[Big Keepers]

Re: Wiring From Scratch

The diagram showing all gauges and acc's going to +12 is just to show that they need +12 to work.

You can use a combined buss that has positive on one side and negative on the other just keep in mind how many items will actually need to be powered and grounded. Blue Sea states that you can double up on one post, meaning you can use two ring connectors on one screw and there is enough room to properly tighten the screw. In my boat I have almost used up all the screws on the positive buss and the negative buss is half way there. I only have about 7 or 8 items that need power.

As far as your gauges go, you'll need the service manual for your engine that hopefully with have a wiring schematic telling you which colors go where. The speedometer usually is a Peto tube that sticks down from the stern of the boat into the water and works off water pressure as you travel through it. I didn't even bother with one because a GPS is 1,000 times more accurate and gives you to the tenth of a mph. Your tach is another story. It could be the wires or it could be the gauge is stripped out inside like mine was. I replaced it actually just recently. All the other gauges are fairly simple to figure out, usually one or two wires and a ground going to them.