Electrical Mastery Series
Eight Episodes built in order. Every number you calculate feeds the next decision. Don’t skip ahead — the sequence is the system.
BY EPISODE 8 YOU’LL KNOW SIX THINGS MOST CRUISERS NEVER FIGURE OUT!
Boat Electricity for Normal Humans
Power Blueprint
Eight episodes. Every formula. Every safety standard. From your first load calculation to a fully specified system ready to install — without needing an electrician’s background.
Your Power Refit Starts Here:
1 ~> Calculate your exact TDAHC
Build a real Load Sheet with honest duty cycles — not guesses. The number every decision flows from.
2 ~> Size your battery bank correctly
Apply the 1.5× buffer and 2-Day Rule to get usable capacity, then convert to nominal for your chemistry.
3 ~> Design a multi-source charge system
Solar, alternator, shore power and generator — all matched to the same chemistry profile, no conflicting sources.
4 ~> Understand the I²R fire cycle
Know why the fuse doesn’t protect you — and what does. The physics of corrosion, heat, and wire fires.
~> 5 Wire to ABYC E-11 standards
AWG sizing for 3% voltage drop, the 7-inch fuse rule, tinned copper, gas-tight crimps. Every non-negotiable.
5 ~> Protect your alternator from lithium
The thermal killer explained. DC-DC charger vs external regulator — pick the right strategy for your boat.
All 8 episodes, all study materials, and all downloads are 100% free forever.
We earn revenue from affiliate product links from this site — not from putting knowledge behind a paywall.
Course One: Foundations
DC Power, Ohm’s Law & Why 12V vs 24V Matters
Understanding DC power, Ohm’s Law as a safety issue, and why the voltage decision shapes everything from wire size to system cost.
- Why 24V systems are more efficient for larger boats
- Ohm’s Law applied to real marine electrical decisions
- How to read a simple electrical diagram without an engineering degree
SPOTIFY – APPLE PODCAST (37:05 minutes) Study Guide | Cheat Sheet | Checklist |
- => Design your System with Sparky
Free download before you listen
Marine Electrical Vocabulary
New to marine electrics? Grab this one-page reference card first. Every term used in Episode 01 — volts, amps, amp-hours, Ohm’s Law, I²R — in plain English. Keep it open while you listen.
Course Two: The Power Audit => Run your numbers in Sparky
Calculate Your Exact Daily Power Consumption
Build your Load Sheet, calculate your TDAHC, and size your system correctly — before spending a dollar on equipment. This step alone saves most cruisers $2,000+.
- How to measure amp-hours for every load aboard
- The ‘daily budget’ method for sizing your system correctly
- Why most cruisers underestimate consumption by 30–40%
- SPOTIFY – APPLE PODCAST (20:43 Minutes)
Study Guide | Cheat Sheet | Checklist | Course Worksheet | => Design your System with Sparky
The most important tool in this serie
10-Minute Power Audit Worksheet
Print this before the next step. List every load aboard, estimate hours/day, apply the 1.5× losses buffer, and get your TDAHC in 10 minutes. Your number feeds directly into Sparky.
Course Three: Battery Chemistry
AGM vs LiFePO₄ — With Real Cost Math
A no-hype comparison of AGM, Gel, and LiFePO₄ for offshore cruising — with real cost math over 5 years. Move past sticker shock.
- Why LiFePO4 is the right choice for most live-aboards
- The real total cost of AGM vs lithium over a 5-year horizon
- When AGM still makes sense — and when it absolutely doesn’t
- SPOTIFY – APPLE PODCAST (24 Minutes)
- Study Guide | Cheat Sheet | Checklist | => Design your System with Sparky
LiFePO4 looks expensive. The maths says otherwise
5-Year Battery Cost Calculator
You think AGM is cheaper. Most liveaboards reach lithium break-even within 3 years. This one-page calculator shows total cost of ownership at Year 1, 3, and 5 for your specific bank size — with real replacement cycle math included.
Course Four: Charging Strategy
Solar, Alternator, Shore Power & Generator
How to safely charge from all four sources without damaging your bank or your alternator. Multi-source prioritization for offshore passages.
- Bulk, absorption, and float: what they mean specifically for lithium
- Why you need separate charging profiles per charging source
- The multi-input prioritization strategy we use for offshore passages
- SPOTIFY – APPLE PODCAST (31:34 Minutes)
Study Guide | Cheat Sheet | Checklist | => Design your System with Sparky
Sailing to the tropics? Your electrical system needs a different set of rules.
Tropical Sailor's Power Checklist
Cruising in the Caribbean, Pacific, or Indian Ocean? Your electrical system was probably designed for a Northern European marina. This checklist covers the 6 adjustments tropical sailors must make — including the 1.17× wire derating factor and the refrigeration duty cycle reality check.
Course Five: Wiring Safety
ABYC-Compliant Wire Sizing & Overcurrent Protection
The wiring standards that separate a safe boat from a floating fire hazard. Every non-negotiable rule from ABYC E-11.
- How to calculate correct wire gauge for any DC circuit run
- Where every fuse goes — and why the 7-inch rule is non-negotiable
- Tinned copper vs bare copper: what saltwater does to your connections
- SPOTIFY – APPLE PODCAST (34:21 Minutes)
Study Guide | Cheat Sheet | Checklist | => Design your System with Sparky
The five wiring mistakes that cause most boat fires — and how to find them on your boat today.
Wiring Safety Self-Audit Guide
A self-guided visual audit with a Red / Amber / Green risk framework. Five warning signs of dangerous connections, the 7-inch fuse rule compliance check, wire type identification, and a voltage drop spot-check method. Found a Red issue? Don’t leave the dock.
Course Six: DC-DC Chargers
Isolating Banks Without Compromising Charging
Why a B2B charger is mandatory in any LiFePO₄ retrofit — and how to wire two banks that never interfere with each other.
- Why a B2B charger is mandatory in any LiFePO4 retrofit
- The difference between a battery combiner and a proper DC-DC charger
- How to wire two banks that never interfere with each other
SPOTIFY – APPLEPODCAST (27:22 Minutes) Study Guide | Cheat Sheet | Checklist | => Design your System with Sparky
Before you download a single terminal
Lithium Retrofit Safety Checklist
Five non-negotiable checks before your first engine run with a lithium bank: DC-DC charger fitted, BMS installed and tested, every charge source reconfigured, ANL/MRBF fuse within 7 inches of positive terminal, shunt monitor installed. Each maps directly to what you just learned.
Course Seven: The Alternator Problem
Why Standard Alternators Fail with Lithium Banks
The most expensive preventable failure on cruising boats. The only safe solutions — external regulation or DC-DC isolation — are explained with real failure scenarios.
- How lithium batteries can destroy your alternator in a single overnight passage
- External regulators: what they do and why you need one
- The DC-DC isolator alternative for smaller or budget-conscious builds
SPOTIFY – APPLEPODCAST (29:57 Minutes) Study Guide | Cheat Sheet | Checklist | => Design your System with Sparky
Before your next passage
Alternator Danger Quiz
Five non-negotiable checks before your first engine run with a lithium bank: DC-DC charger fitted, BMS installed and tested, every charge source reconfigured, ANL/MRBF fuse within 7 inches of positive terminal, shunt monitor installed. Each maps directly to what you just learned.
Course Eight: System Design – Capstone => Use Sparky
Design Your Complete System
Putting it all together with a complete walkthrough using Sparky (MarineAmp). The correct sequence from load calculation to a purchase-ready spec sheet.
- The correct sequence: load → battery → solar → charging sources
- Real-world output from a 400Ah liveaboard build we documented
- Common design errors that waste money and reduce long-term reliability
- SPOTIFY – APPLEPODCAST (24 Minutes)
Study Guide | Cheat Sheet | Checklist | => Design your System with Sparky
Your Capstone output
Marine Electrical Spec Sheet Template
The exact template Sparky fills out as you work through the series. Covers all six design steps: TDAHC, bank size, charging sources, protection strategy, wire sizing, and smart devices. Your completed spec sheet is what Captain Yossi reviews — and what you hand to an installer.
YOUR NUNBER VALIDATED
Features
Not Sure What Size you need?
Ask Sparky
Consultation
The AI marine electrical planning tool is configured to work with ABYC E-11 standards. Enter your loads, get a validated battery bank size, solar array recommendation, and charging spec — matched to your actual boat before spending anything
Have your spec sheet reviewed by Captain Yossi before you commit to hardware. He has guided dozens of cruisers through lithium-ion retrofits, alternator upgrades, and full-system redesigns. A 90-minute session pays for itself the moment it prevents one expensive mistake.
Educational Disclaimer: All course content, study materials, and tools provided by Sea-U Media LLC are for educational and informational purposes only. Marine electrical systems involve serious safety risks, including fire, electrocution, and vessel loss. Always consult a qualified ABYC-certified marine electrician before undertaking any electrical work aboard your vessel. Sea-U Media LLC assumes no liability for errors, omissions, or outcomes resulting from use of this content.