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Wire Purchase For Electronics Mods

HangOutdoors

Jetboaters Admiral
Messages
7,300
Reaction score
8,415
Points
492
Location
Royal Oak, MI
Boat Make
Yamaha
Year
2020
Boat Model
AR
Boat Length
21
Looking for some recommendations on wire brand/quality and were to purchase from. I was at West Marine and they are a bit pricey and they only had down to 6 AWG. I have read a good deal of threads here as well, so I think I got a pretty decent handle on the actually wiring, routing and wiring protection and what others have done. I take a lot of inspiration off of @Julian Electronics build.

Part 1: Choosing the Correct Wire Size for a DC Circuit - Blue Sea Systems

Here is what I am sourcing wire for: If I am understanding the charts correctly (please correct me if I am wrong), you calculate circuit as double the run to determine gauge.
  1. 20' run from Battery to Blue Seas Fuse Block under helm (Rating 100 amp). So it looks like 2AWG. (Chart Plotter, Trim Tabs, USB, VHF, etc.)
  2. 15' run from Trolling Motor plug to Battery Compartment (Rating 60 amp). 6AWG (Minn Kota Terrova 24v #80 thrust on bow).
  3. 10' run from Battery to Blue Seas Fuse Block in Port Compartment (Rating 100 amp). 4 AWG (USB, Vapor alarm, tablet and additional LED Lighting, etc.)
Not upgrading stereo yet, or may not ever, depends on how long we keep this specific boat. I do understand if I do, do that, I would run another run up under helm to the amp.

I am also using these near the batteries.
Amazon.com: YMHTD 100A Reset Fuse 20-150AMP Inline Circuit Breaker Reset Fuse Holder for Car Audio Marine Boat Inverter Replace Fuses 12V-24V DC Breaker Switch Overload Protection Fuse: Automotive

Amazon.com: Blue Sea Systems 150 Amp Common BusBar with 4 studs and a cover, 2307: Sports & Outdoors

For Trolling motor
Amazon.com: Minn Kota 1865106 MKR-19 Waterproof Circuit Breaker Marine Motor Accessory, 60 Amps: Sports & Outdoors
Amazon.com : Minn Kota 1865128 MKR-26 Freshwater and Saltwater Motor Plug and Receptacle Marine Battery Accessory : Sports & Outdoors

And These
Amazon.com: Blue Sea Systems 6 Circuit Blade Fuse Block With Negative Bus 100 Amp Max Per Block 30 Per Circuit: Automotive

Was looking around Amazon, and a bunch of different choices. Any advice would be greatly appreciated.
 
The wires for #1 and #3 sound very large to me for what you’re powering. 2 and 4 ga are pretty heavy cables and none of that stuff seems like it would draw all that much current.
 
Just looked at rough estimates and trim tabs use less than 15-20 amps (recommended fuse size) chart plotters only draw a couple amps max, same for VHF, USB barely uses any.
Just add up the amp draw of all the items you plan to run for each circuit and then leave a margin of safety for future expansion. I would guess you’re looking at 8 ga max to be safe but that’s just a guess.
 
I wouldn't bother with tinned wire, as long as you tin the ends after crimping and use good quality heat shrink (adhesive lined).


2 Awg does seem large... how did you figure 100A continuous load? Many subsystems on boats don't care about voltage drop. For an amp, it would matter. Those should be mounted as close as possible to the batteries.
 
I recently purchased a number of custom-built power cables from Best Boat Wire | Marine Grade Wire Products . I highly recommend them. They offer quality tinned copper marine wire.

They have a nice online form to specify wire gauge, length, and what terminals you want on each end. I received my cables within a few days, it was surprisingly fast. I believe they are located in Georgia and advertise that the wire is from the US.

For me, it was a great choice since I do not have the capability (or desire) to try and crimp 4 AWG terminals.
 
@marcham I didn't figure the continuous load. Remember I am a bit out of my element with this. The Blue Seas Fuse Block is a 100A the Breakers are 100A, figured I would just do it all for possible future things and do it once. Since the wire increase per foot is nominal depending on gauge.

The Minn Kota calls for 6AWG at that run and a 60 amp breaker.

Of course any suggestions and/or criticism is greatly appreciated.
 
Looking for some recommendations on wire brand/quality and were to purchase from. I was at West Marine and they are a bit pricey and they only had down to 6 AWG. I have read a good deal of threads here as well, so I think I got a pretty decent handle on the actually wiring, routing and wiring protection and what others have done. I take a lot of inspiration off of @Julian Electronics build.

Part 1: Choosing the Correct Wire Size for a DC Circuit - Blue Sea Systems

Here is what I am sourcing wire for: If I am understanding the charts correctly (please correct me if I am wrong), you calculate circuit as double the run to determine gauge.
  1. 20' run from Battery to Blue Seas Fuse Block under helm (Rating 100 amp). So it looks like 2AWG. (Chart Plotter, Trim Tabs, USB, VHF, etc.)
  2. 15' run from Trolling Motor plug to Battery Compartment (Rating 60 amp). 6AWG (Minn Kota Terrova 24v #80 thrust on bow).
  3. 10' run from Battery to Blue Seas Fuse Block in Port Compartment (Rating 100 amp). 4 AWG (USB, Vapor alarm, tablet and additional LED Lighting, etc.)
Not upgrading stereo yet, or may not ever, depends on how long we keep this specific boat. I do understand if I do, do that, I would run another run up under helm to the amp.

I am also using these near the batteries.
Amazon.com: YMHTD 100A Reset Fuse 20-150AMP Inline Circuit Breaker Reset Fuse Holder for Car Audio Marine Boat Inverter Replace Fuses 12V-24V DC Breaker Switch Overload Protection Fuse: Automotive

Amazon.com: Blue Sea Systems 150 Amp Common BusBar with 4 studs and a cover, 2307: Sports & Outdoors

For Trolling motor
Amazon.com: Minn Kota 1865106 MKR-19 Waterproof Circuit Breaker Marine Motor Accessory, 60 Amps: Sports & Outdoors
Amazon.com : Minn Kota 1865128 MKR-26 Freshwater and Saltwater Motor Plug and Receptacle Marine Battery Accessory : Sports & Outdoors

And These
Amazon.com: Blue Sea Systems 6 Circuit Blade Fuse Block With Negative Bus 100 Amp Max Per Block 30 Per Circuit: Automotive

Was looking around Amazon, and a bunch of different choices. Any advice would be greatly appreciated.
Pacer Group out of FLA has all the wire, shrink wrap, and lugs you will need at decent prices. They also have a calculator for wire size (I think).

I have dealt with them on several occasions and they manufacture their own wire. Good experiences with them.
 
@marcham I didn't figure the continuous load. Remember I am a bit out of my element with this. The Blue Seas Fuse Block is a 100A the Breakers are 100A, figured I would just do it all for possible future things and do it once. Since the wire increase per foot is nominal depending on gauge.

The Minn Kota calls for 6AWG at that run and a 60 amp breaker.

Of course any suggestions and/or criticism is greatly appreciated.
The trolling motor definitely needs that big wire. I ran 8 ga for a shorter run on my last boat with a 70lb minn Kota and the wire would get a little warm when I used the motor for a long time.

I don’t think you could find enough stuff to take 100amps on those new accessory circuits if a big stereo isn’t in the picture.
 
You have to look up the demand of each device, add them up, add 20% for spare capacity, and then round up to the next fuse size. You dont have to size for the bus rating of the fuse block. You have to size for the upstream fuse rating and then count for any voltage drop. Then size the ampacity of the wire for the fuse rating. I suggest that you google the specifications of all your devices, add them, and post it here so we can find what you need
 
So would the best solution than be to grab a 100'ft spool each of red and black 6AWG and use it for everything I am doing? Easier to handle and cost effective with some to spare.
 
I suggest that you google the specifications of all your devices, add them, and post it here so we can find what you need

I can do that for what I have now, but what about future expandability for what I am unsure? When I put in a fuse panel in my house I go with 200 AMP service, but really I could of used 100 AMP service, but I don't know the future. Figured I would do the same here? Or am I looking at it wrong?

No reason to go nuts and WAY Overbuild it, but definitely with some thought to future expandability was my thought process.
 
So would the best solution than be to grab a 100'ft spool each of red and black 6AWG and use it for everything I am doing? Easier to handle and cost effective with some to spare.
Yes that would work and give you plenty of excess capacity.

I assume you’re just running two fuse blocks because it’s too hard to get from the helm over to the port side with the individual circuits?
If it’s any cheaper you could easily get away with a much smaller wire size for what you’re proposing on the port side. Maybe get 50’ of the 6ga and 10’ of 10ga. All the big stuff (really just the trim tabs) is on the helm side.
 
@AZMark Yes you are correct. Just wanted to put a fuse block over there on the port side for phone and tablet charging and some other things which is just a quick run from the battery compartment.
 
@AZMark Yes you are correct. Just wanted to put a fuse block over there on the port side for phone and tablet charging and some other things which is just a quick run from the battery compartment.
Makes sense. Even 10 ga over that short of a section would give you extra capacity to add things later. Anything that doesn’t move (like motors, speakers, tab actuators) isn’t going to draw many amps.
 
I can do that for what I have now, but what about future expandability for what I am unsure? When I put in a fuse panel in my house I go with 200 AMP service, but really I could of used 100 AMP service, but I don't know the future. Figured I would do the same here? Or am I looking at it wrong?

No reason to go nuts and WAY Overbuild it, but definitely with some thought to future expandability was my thought process.

I see that you have a 4AWG and 2AWG feeding 2 different fuse blocks. That's a ton of capacity for a boat. According to the NEC ampacity chart, assuming 75C rated wire, you have 200amps of capacity. Everything you listed is low current draw. Are you planning to power a washer/dryer in the future? My guess would be 40amps is safe, 60amps is extra. And for reference, I did a similar job in my truck and I had used ancor marine grade wire that is rated for 75C wet and 105C dry. So I think it would be safe to use the 90C chart here.

I personally would run 1 wire to feed 2 fuse blocks. Calculate your total demand, assuming 80amps (ton of spare capacity):

Fuse panel next to the battery
[HASH=5698]#4AWG[/HASH] from the battery to circuit breaker
[HASH=5698]#4AWG[/HASH] from circuit breaker to fuse panel lug
another lug from the fuse panel (2 lugs on the fuse panel) and run another [HASH=5698]#4AWG[/HASH] to the 2nd fuse panel at your helm.

And 1 dedicated feed to your trolling motor with a circuit breaker.

ampacity.PNG
 
I see that you have a 4AWG and 2AWG feeding 2 different fuse blocks. That's a ton of capacity for a boat. According to the NEC ampacity chart, assuming 75C rated wire, you have 200amps of capacity. Everything you listed is low current draw. Are you planning to power a washer/dryer in the future? My guess would be 40amps is safe, 60amps is extra. And for reference, I did a similar job in my truck and I had used ancor marine grade wire that is rated for 75C wet and 105C dry. So I think it would be safe to use the 90C chart here.

I personally would run 1 wire to feed 2 fuse blocks. Calculate your total demand, assuming 80amps (ton of spare capacity):

Fuse panel next to the battery
[HASH=5698]#4AWG[/HASH] from the battery to circuit breaker
[HASH=5698]#4AWG[/HASH] from circuit breaker to fuse panel lug
another lug from the fuse panel (2 lugs on the fuse panel) and run another [HASH=5698]#4AWG[/HASH] to the 2nd fuse panel at your helm.

And 1 dedicated feed to your trolling motor with a circuit breaker.

I believe that particular chart is for construction wire.
 
I believe that particular chart is for construction wire.

It is from the NEC National Electrical Code. I believe automotive and marine wire is PVC jacketed, THW (Thermoplastic, Heat Resistant, Water Resistant). I have seen that automotive/marine wire is more heat resistant than building wires so there is kind of derating in this chart vs real world.
 
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