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My journey to becoming a true sparky

Short version:

I took most of my inspiration from KlabauterKiste:

He has made a fantastic guide for anyone thinking of doing their own electric works. 

What worked:

Most of time was spent thinking before doing.

I highly recommend using to map out the existing setup and then start planning the new setup.

I made an excel with how many amp hours I need and on that basis decided on the size of the batteries. 

What I would do differently:

I bought a switchboard before I had even done any thinking. That made deciding which consumers would share a switch a more restrictive process. 

Don't waste your time trying to cut and strip wires with the old cutter method. Just buy a proper tool. It speeds up the process and leads to a better result. 

The Longer version:

Throughout this refit, we have had to strike a balance between what-would-be-nice and what-is-cost-efficient. 

In an ideal world, I bring in an electrician who just takes care of the job. 

In an ideal world, the electric on board would not have to be redone. 

In an ideal world, we might have bought a bigger boat.

In an ideal world, money would not be an issue...

So here we are, in our wonderful un-perfect reality, confronted with hundreds of little choices. Each choice seems to boil down to the same options: leave it as is, replace only what is necessary or rip it all out and start from scratch. 

My previous experience with electrics does not amount to much. I am responsible for changing light bulbs, installing updates and making sure the dvd player works. I have wired some plugs, replaced heating elements in an oven and know not to plug in an extension chord when it is still rolled up. I always put AA batteries in the wrong way around on the first go and my main Troubleshooting strategy is turning things on and off a few times in a row. 

What I am not, is an electrician. 
Rosa took one look at the old "switchboard" and abdicated the role of sparky.

sparky noun [ C ] UK informalUK  /ˈspɑː.ki/ US  /ˈspɑː

an electrician (= a person whose job is to put in and repair electrical wires and equipment)

The old electrics on board were a mess. The various owners had "upgraded" along the way, cutting wires in half and simply adding a new light or a water pump. This meant, that in order to operate the water pump, the cabin lights needed to be on. But at the same time, the mast navigation light also needed to be on, in order to operate the forward cabin lights. That meant lighting up the whole boat like a Christmas tree, only to pump a glass of water. Not only is this energy inefficient, it is also dangerous. 

After blowing the main (and only) fuse, I made the decision to replace everything. Rip it all out and start again!

TAKE PHOTOS - with every job I started, I tried to take as many photos as possible. It is incredible what my mind forgets and having proof of how things used to be is invaluable. 

The first and most valuable advice I received, was to think about the problem in reverse:

1. What do you need on board that requires electricity?

2. How much electricity do you require?

3. How big do your batteries need to be?

4. How will you produce electricity?

5. What ALWAYS needs power?

6. Start connecting it all


I started by enthusiastically tearing out all the old wires and equipment and striping the whole boat to a bare state. Then I started asking myself what a volt actually is... 


This is where the excellent guide by KlabauterKiste came in very handy:

It is in german, but also diligently detailed and painfully precise. 

Start with the basics and become familiar with volt, current, amps, amp hours and how to measure them all. If you have reached this point and decide that this would be too much work, then hire an electrician and don't worry about it. 

1. What do you need on board that requires electricity?

Like so many things in my life: I started with an excel sheet. 

I really thought about everything that we could possibly want electricity for, including things like laptops and phones that need to be charged. Here is my completed list:

  • Navigation Lights

  • Anchor Light

  • V-berth lights

  • V-berth LED Strip

  • Head Light

  • Galley Light

  • Saloon Light

  • Saloon LED Strip

  • Starboard Reading light

  • Port reading light

  • cockpit light

  • Fridge

  • Waterpump Freshwater

  • Waterpump Salt water

  • GPS

  • Transducer

  • Bilge Pump 1

  • Bilge Pump 2

  • VHS

  • Laptop 1

  • Laptop 2

  • Smartphone 1

  • Smartphone 2

  • iPad Navigation

  • iPad 2

  • GoPro

  • Drone

  • Bluetooth speaker

  • Electric toothbrush

The electric toothbrush just managed to sneak onto this list at the last moment. I recommend making a list, checking it twice and then forgetting about it for a while before having someone else read through it. 

2. How much electricity do you require?

In the next step I worked out the consumption of each item and then total the amount needed. 

A lot of electric items will tell you how many amps they require.

Our GPS for example requires 2 amps to run.

Lightbulbs will only have the required Watts noted. It is not complicated to work out the amps from Watts. Plenty of online calculators if math is not your thing. 

Not all electric items will be running the entire time. We will not have a light on in the cabin 24 hours a day. So we made a guestimate of the total hours per day that an item would be running. The Fridge would be running for 24 hours, the Saloon Light for 6 hours. Then we can work out the required amp hours (ah). Fridge runs at 2 amps x 24 hours = 24 ah amp hours. 

We also differntiated between electricity needed while sailing and while at anchor. The navigation lights, GPS and transducer would be turned off while at anchor. Similarly we would probably not be using the anchor light while underway. 

Adding up all the required amp hours:

195 amp hours while sailing

155 amp hours while at anchor

This includes a generous 24 hours of bildge pump continously running. In practice the bildge pumps will be running a total of 0 hours per day, because I really don't want to be in a leaky boat. But if the situation does arise, that the bildge pump needs to run for 24 hours, then I would like to be prepared. 

3. How big do your batteries need to be?

I would have preffered some fancy lithium ion batteries.

But alas... money. 

Nothing wrong with some gel batteries, we just made sure they are the maintenance free variety. 

They also weigh a ton.

Effectively they can only be discharged to half of their capacity. So if we require 200 amp hours in total, we would need a batterie bank consisting of at least 400 amp hours. 

We have two batteries now, they each weigh 55kg. 

4. How will you produce electricity?

The short answer is: a combination of shore power, solar power, charging from the engine and... no that's it in our case. Would love to also install a wind generator, a hydro generator and have a spare diesel generator just in case, but space on board is a limiting factor. And also money. 

I have invested heavily in solar. We have a great solar charge controller and enough panels to charge the full bank on a reasonably sunny day. My aim is to use the motor to charge only at a pinch. 

My solar charge controller can be accessed directly via Bluetooth and that just makes my little heart sing. The charge on the starter motor is monitored by a LED display, which can be seen in the pictures above. 

5. What ALWAYS needs power?

This is a more important question that I thought at the start. 

The obvious answer is: the fridge. How else do you keep the beers cold?

But seriously, this is worth spending some time thinking about, especially in the concept phase. 

When you leave the boat, you want to be able to turn the batterie bank off. At the same time you would hope the bildge pumps kick in when one of the sea cocks fail. 

I have made sure that the bildge pumps and the essential navigation equipment bypass the swichtboard and are connected directly to the batteries. In a worst case scenario, where the entire switchboard fails, then the essentials can keep running while we fix the problem. 

Each item on the list has also been isolated via a seperate fuse, to ensure multiple levels of failure proofing. 

6. Start connecting it all

I can highly recommend using to make a plan of all the electrics. 

It was invaluable to me, to sit in the boat with all my tools prepared and just concentrate on connecting all the right bits in all the right places. 

I am also glad that I worked out how many meters of cable I need before I started. 

I ended up using over 55 meters of cable. Not bad for 8.5m boat. 

The state of the electrics on board was really in a shocking state. The more I looked into it, the more surprised I am that we did not cause a fire on board. 

It gives me a really warm feeling at night, knowing that it all works and makes sense now. 
I made sure to document and label each wire, making the task of the next owner that much easier.

Bildschirmfoto 2020-12-16 um
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