Wiring for dummies!

[Fox_Red131]

Hey everyone,
Well, it's freezing here in KY but I've got the fever to be on the water. Just celebrated a birthday and got the hookup from some family (new CD player and switch panel) for the boat! Needless to say I'm pumped to get rolling on everything. Here's where I need some guidance. Right now I run a mess of wires with inline fuses back to the battery so I got this 6 accessory panel from Seasense. It has all the connections on a buss in the back and as per directions it wants a separate negative buss. The leads off the switch panel for (+) and (-) must be a 16 or 18 g wire...it's small. My question is what would be the best way of doing this with adequate wire gauge going from the battery to my new panel in particular? I understand the lingo fairly well, so any advice is great. Thanks guys.

 

[sam am I]

Re: Wiring for dummies!

I'm not sure I understand completely but.........#1's schematic may help?

http://forums.iboats.com/electrical-electronics-audio-trolling-motors/fuses-needed-not-637538.html

We're all dummies with this stuff btw.............some of us just have more yrs of practice/perfecting baffling w BS than others is all.

 

[Fox_Red131]

Re: Wiring for dummies!

Sorry, probably making it more confusing than it needs to be. I've got a diagram for a smaller number of switches but it's identical to diagram on mine.



Just wondering what gauge wire to hook it up with to the battery.

 

[sam am I]

Re: Wiring for dummies!

Cutting to the chase? 10 AWG!!!

Short story longer?........Unless you're running high high current audio amps or inverters and what have ewe's which require a bit different attention, 10 AWG with 30 amps breaker. as shown in that link above is typical for us old dudes in less than 20' runs.

At 20' and 30 amps(recommended breaker), it'll be dropping about 1.2 volts., (10' , 30 amps, .6 volts)..so gauge appropriately depending on run in feet for the wire, load/breaker current max(not wire max) and voltage loss you can except.

10 AWG wire I believe will do around 55 amps max. BTW, so it's all good to follow what has been laid out unless you're wiring a carrier?

Side note.......
It is recommended you run a "main circuit protect" fuse as shown and following the rule/guideline for the panel to be wired where............

"Mounting placement dimensions for a fuse or circuit breaker (7"/40"/72" ABYC rule): 7 inch maximum if the conductor is not housed in a sheath or enclosure in addition to the wire insulation, 40 inch maximum if the conductor is housed in a sheath or enclosure in addition to the wire insulation, 72 inch maximum if the conductor is connected directly to the battery and housed in a sheath or enclosure in addition to the wire insulation." to avoid http://www.boatus.com/seaworthy/fire/ as best as possible. Ty Auger01

I live slightly on the edge, I have a 50 amp resettable "main circuit protect" fuse inline with my 10 gauge @ about 10 feet (you know, just in case I jam a fish head or my finger in the live well pump impeller, I'll be sure to shear them both off)......However, the 30 amp breaker the diagram shows is a good safe derated number to use/stick with.

 

[The Revenge]

Re: Wiring for dummies!

I'm just wrapping up my new electrical system now.

I have an 8 gauge wire going from the common post on the battery selector to a resettable fuse/circuit breaker. It's 30 amp and trips by heat. From that fuse my 8 gauge wire goes to my 12 post blue sea fuse box/panel.
The wire from the common post to the fuse is 6" long. Then from the fuse to the fuse panel the wire is roughly 14".

All this sound okay?

 

[jc55]

Re: Wiring for dummies!

My pilot house has 14 gauge running everything for the last 24 years...yikes. After doing a lot of research I'm going with 10 as well on a total rewire. But with 10/4 for two accessory circuits. After seeing how most stock boats and ford mustangs get wired, we certainly couldn't do much worse.

 

[Fox_Red131]

Re: Wiring for dummies!

Thanks for all the input, 10 AWG it is! I do appreciate it.

 

[jhebert]

Re: Wiring for dummies!

Thanks for all the input, 10 AWG it is! I do appreciate it.

In distribution of power in a 12-Volt System, a conductor of 10-AWG can only handle 15-Amperes for a distance of 12-feet.

The conductor has to be sized to maintain a three-percent voltage drop. See

Sizing conductors - Moderated Discussion Areas

for some detailed discussion on how to calculate conductor size.

For a concise overview of boat electrical power distribution and wiring, see

continuousWave: Whaler: Reference: Boat Wiring

 

[sam am I]

Re: Wiring for dummies!

In distribution of power in a 12-Volt System, a conductor of 10-AWG can only handle 15-Amperes for a distance of 12-feet.

The conductor has to be sized to maintain a three-percent voltage drop. See

Sizing conductors - Moderated Discussion Areas


for some detailed discussion on how to calculate conductor size.

For a concise overview of boat electrical power distribution and wiring, see

continuousWave: Whaler: Reference: Boat Wiring

Good point Jim,

And true that for "power distribution" which is defined as wire ran bundled and/or in conduits, BUT, for "chassis wiring" defined as single/loose type wire runs where the wire has free air flow around as such, it's 55 amps for 10 AWG.

OP, definitely something to consider, adjust accordingly depending on how you rewire.

The main feeds from my(most boats) batts to panels are typically all "chassis" types as with like batt cables and the like.

 

[jhebert]

Re: Wiring for dummies!

...that for "power distribution" which is defined as wire ran bundled and/or in conduits, BUT, for "chassis wiring" defined as single/loose type wire runs where the wire has free air flow around as such, it's 55 amps for 10 AWG.

This distinction is of no importance in distribution of power on a boat using a 12-Volt power system. In a 12-Volt system the conductor size must always be chosen with consideration of the voltage drop, based on the distance and current in the circuit. It matters little what the rating of the conductor is for maximum current capacity, because that rating is based on heating of the conductor and its insulation quality. In power distribution in a 12-Volt system, any time the length of the conductor is more than a few feet, the voltage drop will require the conductor size to be much larger than any consideration of current capacity would need. The conductor will always be rated for a much higher current capacity than it can actually carry in a 12-Volt system without having too much voltage drop. A figure of three-percent voltage drop is considered the usual threshold for power distribution to loads that need stable voltage.

 

[sam am I]

Re: Wiring for dummies!

This distinction is of no importance in distribution of power on a boat using a 12-Volt power system. In a 12-Volt system the conductor size must always be chosen with consideration of the voltage drop, based on the distance and current in the circuit. It matters little what the rating of the conductor is for maximum current capacity, because that rating is based on heating of the conductor and its insulation quality. In power distribution in a 12-Volt system, any time the length of the conductor is more than a few feet, the voltage drop will require the conductor size to be much larger than any consideration of current capacity would need. The conductor will always be rated for a much higher current capacity than it can actually carry in a 12-Volt system without having too much voltage drop. A figure of three-percent voltage drop is considered the usual threshold for power distribution to loads that need stable voltage.

Drop was addressed. The 15 amp verses 55 amp is/was the bit of disparity here?

But sure, I can see setting a limited, but we're spitting hairs I think with .2 volts. Most devices are in the 10% range. But I would agree, 3 percent is a good safe number/rule of thumb.

He'll have 5% at the 30 amps, 11.4V :noidea:

 

[Fox_Red131]

Re: Wiring for dummies!

I considered the voltage drop but it didn't weigh that heavy on me, probably because I'm a rook! The CD player was a gift, I will possibly look into a swap for usb. As far as the distance goes, I will be going from my battery to the switch panel in about 6 feet, possibly 5. The negative buss will be in the same area under the steering console. So all that considered, I plan to hook the switch to:

1. Cig lighter for pump
2. Nav. lights
3. Small LED interior lights
4. Bilge
5. Aerator
6. CD/Stereo
7. Fish Finder

What can we settle on in terms of wire gauge for my main supplies to the switch and negative buss? Thanks y'all, love all the good info.

-Brad

 

[Georgesalmon]

Re: Wiring for dummies!

#10