Need opinions

[TriadSteeler]

I am completely re-wiring a 1974 Ebbtide Lakemaster Tri-hull with a 1974 Merc 500. Below is my wiring plan. I am switching to a dual battery setup and moving the ignition switch from the control box to the dash as well as installing a push-to-choke ignition switch. Guru's please give it a once-over and let me know if there is anything wrong with the setup. I don't want to fry anything (including myself) before I even get her backed out of the driveway.

 

[jtexas]

Re: Need opinions

nice illustration.

Is your depthfinder on switched power? I take it you don't use it when the motor's off? Anyway, wouldn't surprise me if you get some electrical noise showing up on the graph. A lot of d/f call for a 1 amp fuse.

You were so thorough, then omitted the speedometer pitot and radio antenna!

 

[TriadSteeler]

Re: Need opinions

nice illustration.


Is your depthfinder on switched power? I take it you don't use it when the motor's off? Anyway, wouldn't surprise me if you get some electrical noise showing up on the graph. A lot of d/f call for a 1 amp fuse.

You were so thorough, then omitted the speedometer pitot and radio antenna!

Thanks for the reply jtexas. Was in Dallas a few years back. Liked the area a whole lot. Except for the Cowboys of course


What is the best way to wire the depthfinder. It is a humminbird 610 with a puck transducer. I probably should get that off of the ignition link and supply it from the switch panel. Should I also put an inline fuse for all of the gauges?

No radio antenna. I will have a mount on the passenger dash for a removeable Sirius radio and an MP3 player. I may install a Sirius antenna, but plan to use the magnetic one to start with.

This is also the first time I have delved into a dual battery setup. Do the connections look correct?

Also, Will that aftermarket push-key-choke ignition switch work with the '74. The package claims it is for a mercury OB.

 

[jtexas]

Re: Need opinions

Gauge power from keyswitch accessory terminal is ok without fuses. the fishfinder running thru the panel might still see some noise, but it's not a sure thing. Were it mine, I'd do it like your accessory sockets with an inline fuse. Consider circuit breakers on both battery (+) feeds, to protect against a direct short. Big enough not to trip if all your toys are on at the same time.

 

[drewpster]

Re: Need opinions

A couple of things. The changes are below.
Note; If the boat is going to stay in the water, power the bilge pump directly from the battery. Fuse it at its source, and use an automatic switch with a manual switch override.
Use the proper size fuses and marine grade wire.
Use full size (6 gauge minimum for single outboard eng.) marine battery cable for all your main battery cables positive and negative on both batteries. Do not undersize your accessory battery leads. That way you can start your engine safely with either battery, or both.
The main battery switch selects the battery you want to use and isolates the batteries in case of an electrical fire. In the "off" position it cuts all power.
Put all your loads on the common post of the switch. This includes the battery cable that goes to your engine's starter. The engine should provide voltage back through the starter cable to recharge your batteries and provide power to the ignition and everything else. It is up to you to select which battery you want to use by switching to it after you shut the engine down. You can select "both" to charge them both. When you select "Off" it will isolate all loads from the batteries per. ABYC specs. (note: Never switch to "Off" while the engine is running.)

Switch post 1 = start batt +
Switch post 2 = accessory batt +
Common post = starter cable, common buss + (bilge pump optional)

Here is a good book on the subject.
http://www.iboats.com/12_Volt_Bible_for_Boats_2nd_ed/dm/*******.366734582--category_id.216524--list_time.1206507429--**********.404744443--view_id.11202

This one is good too.
http://www.amazon.com/Marine-Electrical-Electronics-Bible/dp/1574090607

 

[TriadSteeler]

Re: Need opinions

A couple of things. The changes are below.
Note; If the boat is going to stay in the water, power the bilge pump directly from the battery. Fuse it at its source, and use an automatic switch with a manual switch override.
Use the proper size fuses and marine grade wire.
Use full size (6 gauge minimum for single outboard eng.) marine battery cable for all your main battery cables positive and negative on both batteries. Do not undersize your accessory battery leads. That way you can start your engine safely with either battery, or both.
The main battery switch selects the battery you want to use and isolates the batteries in case of an electrical fire. In the "off" position it cuts all power.
Put all your loads on the common post of the switch. This includes the battery cable that goes to your engine's starter. The engine should provide voltage back through the starter cable to recharge your batteries and provide power to the ignition and everything else. It is up to you to select which battery you want to use by switching to it after you shut the engine down. You can select "both" to charge them both. When you select "Off" it will isolate all loads from the batteries per. ABYC specs. (note: Never switch to "Off" while the engine is running.)

Switch post 1 = start batt +
Switch post 2 = accessory batt +
Common post = starter cable, common buss + (bilge pump optional)

Here is a good book on the subject.
http://www.iboats.com/12_Volt_Bible_for_Boats_2nd_ed/dm/*******.366734582--category_id.216524--list_time.1206507429--**********.404744443--view_id.11202

This one is good too.
http://www.amazon.com/Marine-Electrical-Electronics-Bible/dp/1574090607

Thanks Drewpster. The battery switch and additional in-line fuses was where I was struggling. I will be making your suggested changes. The bilge pump is one of those Rule auto cycling pumps. This boat will be trailered except for the weekends in the water. The switch will be in the on position ( I think it cycles 1/per min.)when the boat is in the water. I didn't want to have to crawl under and unhook it while the boat was on the trailer and have it drain the batteries while it is in my driveway.

I already have all of the wiring. The battery leads are all 4 gauge tinned copper wire. The accessory wire is all 14 g and the leads to and from the battery switch to the buss bars is 10g.