Electrical Systems

Most boats have two types of electrical systems: AC (alternating current), and DC (direct current).  I didn’t really understand which was which until I figured out the power sources.  AC comes from the shore power cord or from the batteries through an inverter, if you have one.  When you don’t have an inverter, then none of your regular plugs will work if you’re not hooked up to shore power.  DC comes from the batteries.  If you have any appliances that use the cigarette lighter-type plug, then you can use it while just on battery power.  That’s about the extent of what I know about electricity, other than it stings when you get shocked and it can kill you.  Thankfully, Rich knows a lot about electrical systems.

AC System

The existing AC system wiring was in poor condition and wasn’t marine grade (meaning the wire wasn’t tinned which makes it resistant to corrosion).  We installed Ancor Marine triplex marine grade wiring.  We also added some outlets for a few reasons:  1) we use a lot of appliances while living aboard at the marina (alarm clock, coffee maker (we use an Aeropress now which takes no electricity), heater/dehumidifier, computers, air purifier and on and on); 2) the existing outlets were located in inconvenient places; and 3) the existing outlets were old and got hot during use (scary).  Plus none of the existing outlets were GFCI, so we added one of those to each side of the boat as well.

Shore Power

We changed our shore power set up from the standard twist-type marine plug to a Smart Plug.  The Smart Plug is fully waterproof, locks into place and has 20x more contact area to greatly reduce electrical resistance and the chance of arcing.  We also moved the plug from the cockpit to the outside of the cockpit combing, so now it’s not a tripping hazard when we get in and out of the cockpit.


The winter of 2017 was a doozy when it came to weather. Our area had almost 200% more rain than usual. Though we only lost power a couple of times and never for very long, we decided to buy a Honda i2000 generator. Our batteries are slowly dying and if we lost power for any length of time, they would drain quickly. The marina we live in is pretty remote and we have lost power at all times throughout the year. Once we lost power when a great blue heron flew into the overhead power lines. We knew we were going to get a generator eventually, so we thought why not get it now for when we lose power. Of course, since we bought the generator we haven’t lost power once…knock on wood.

DC System


The boat came with 3 new AC Delco batteries.  One is for the starter and the other two are the house bank, though we believe they’re all tied together somehow (the battery switches are wired weirdly and we can’t figure them out).  Right now (2013), this setup is working for us since we are on shore-power 100% of the time and the batteries just run the lights and fans.  Down the road, we are going to beef up the DC system.

We also need to modify our battery box or maybe move it or add another one.  The surveyor noted that the batteries aren’t strapped down and the terminals don’t have those nifty covers over them.  I don’t really like where the batteries are located (under the quarter berth).  They are easy to access, but they are hogging valuable storage space.  I think moving them to the engine room might be a good idea as long as we can prevent them from getting too hot.

UPDATE: March 2017

We’ve finally made some decisions on batteries. We are going to buy Firefly Oasis Group31 batteries. These batteries are more expensive than standard AGMs but a small fraction of the cost of lithium batteries. Plus they’re Nigel Calder uses them and gave them high marks.

Here’s what their website has to say:

Firefly’s technology is an innovative material science that removes almost all limitations of current Lead Acid Battery Products. Carbon Foam is an Aero-Space Age material. It is a Composite made of high purity carbon carrying material. It’s used in nozzles of missiles and other energy absorbing applications. It’s bulk density is very low, below 0.04 g/cc and porosity is above 90%

Carbon is not attacked by Acids or Alkalies and it’s highly conductive. Grid is made of Carbon Foam and Active Material is pasted on this grid. Carbon Foam has very high surface area for electro chemical reactions. Due to the inherent and amazing properties of Carbon and 3D Honeycomb structure of the Carbon Foam, it has thousands of micro pores which ultimately provides the following benefits to the Firefly Batteries:

  • High Ah and energy efficiency
  • Longer cycle life
  • Fast recharge capability and high charge acceptance rate
  • Resistance to hard sulfation
  • Continuous power through discharge process
  • Instantaneous power due to low internal resistance
  • Recovery to full capacity after discharge
  • High temperature resiliency
  • Operation in partial state of charge for days without loss of capacity
  • Excellent cold temperature capacity utilization

We’ve also decided to keep the batteries under the quarter-berth. Even though we removed the water heater from the engine room and have plenty of room in there for batteries, we think the high temps in the engine room may be a problem. We’re going to build a new battery box that will fit hopefully four 110Ah batteries (3 house-bank and 1 starter).

Battery Switches

We also bought a Blue Sea Systems Add-A-Battery kit which will simplify the battery switches.

Here’s what Blue Sea Systems website says:

Dual Circuit Plus™ Battery Switch

  • Simplifies switching
  • Isolates engine and house circuits
  • Combines batteries for emergency starting
  • Tin-plated copper studs for maximum conductivity and corrosion resistance

ACR Automatic Charging Relay

  • Automatically combines batteries during charging
  • Isolates batteries during engine cranking and when not charging
  • Shares the charge between two batteries more efficiently than a battery isolator
  • Allows efficient dual battery charging without needing regulator adjustment or rewiring

Well, we changed our minds again though through no fault of our own.  We were really excited to try the new Firefly batteries, but we are having a hard time finding them locally.  Plus, we’ve been told that since the company moved the manufacturing to India the quality control has been really bad.  Some of the batteries fail right away.

After a lot of searching we decided to go with Mastervolt AGM Slimline batteries or something similar.  The shape is conducive to our battery box and the amp hours seem appropriate.  We think 3 of these type of batteries will fit.  More info coming when we make our final decision.


We considered getting separate charger and inverter, but we just don’t have the space to do that.  Currently we’re leaning toward the Mastervolt Mass Combi inverter/charger.  Here’s what Mastervolt has to say:

Benefits of the Mass Combi

  • Compact, lightweight and no hum thanks to HF technology.
  • High yield and more power from your batteries.
  • Intelligent 3-step+ battery charger with low DC ripple current for fast charging times and long battery life.
  • Charges two individual battery banks simultaneously.
  • Quiet, powerful inverter with 200 % peak power.
  • Power Assist: extra power assistance from the batteries in case of limited grid or generator power (prevents blown fuses).
  • Pure sine wave energy prevents failures and damage to sensitive equipment such as adapters.
  • Dual AC outputs to separate critical equipment from heavy loads.
  • Higher yields possible via parallel switching (only 2500 W models).
  • Professional connections ensure fast installation and operational security.
  • CE approved and E-marking for mobile applications.

We’re still working on this…to be continued.


Since the headliner is down and we’re up to our eyeballs in unfinished boat projects we thought now is the perfect time to start yet another project – upgrading the cabin lights.  We wanted to go with LED lights, until we started researching how expensive they were (yeow!)  Evidently, LEDs used in your home are not the same LEDs used on a boat.  Household LEDs, which run off AC power, cannot handle fluctuating DC voltage found on a boat.  There have been several stories about boats catching fire or burning down because of cheap LEDs.  Therefore, marine LEDs must have some sort of voltage regulator or current converter.  Rich found Marinebeam.com. and they sell LEDs with constant current converter chip-sets to retrofit your existing fixtures and they’re affordable.  This is the list of interior LEDs we have on Ramble On:

Interior LED Lighting

Location12” Rigid LED Strip LightsConstellation LEDR-W Switchable LEDX-beam 10 LED Power Cluster
Light Specifications:
  • Warm White
  • 10-30 VDC
  • 5 watts
  • 0.4 amps
  • 380 lumens
  • ? beam angle
Light Specifications:
  • Warm White
  • 10-30 VCD
  • 2.7 watts
  • 0.23 amps
  • 190 lumens
  • 120° beam angle
Light Specifications:
  • Warm White
  • 10-30 VCD
  • 0.6-2.5 watts (R/W)
  • 0.05-0.21 amps (R/W)
  • 145 lumens
  • 120° beam angle
Light Specifications:
  • Warm White
  • 10-30 VCD
  • 2.2 watts
  • 0.18 amps
  • 120 lumens
  • 120° beam angle
Galley5 – counter top task lighting
2 – sink task lighting
1 – 7” Dome Light (original)
Nav Station1 – electrical panel task lighting1 – 7” Dome Light (original)
Salon6 – under-cabinet lighting
(3 on each side)
2 – 7” Dome Lights
V-berth4 – under-cabinet lights
(2 on each side)
1 - 7" Sea-Dog Dome Light (new Sea-Dog) in hallway2 – Victory Xenon Swivel Sconce Fixtures
Head2 – counter top task lighting1 – 7” Dome Light (new Sea-Dog)
Quarter Berth1 – under-cabinet lights
Engine Room

The strip lights we’re using as under-cabinet lighting are chained together by USB cables.  The bad news is Rich had to make the USB connectors because they came with only one male connector and the on/off switch.  In order to chain them together, we needed USB connectors with a male on one end and a female on the other end.  Here’s a video of how he did this…it’s pretty amazing.

Breaker Panel

During the survey we had a heck of a time figuring out what worked and what didn’t because fuses were blown, missing, or just loose.  When we moved the boat from Richmond to Isleton we didn’t have a depth sounder for part of the way because the fuse was loose.  And during that trip we found out how wet things can get in the companionway, which is where the breaker panel is located.  Granted, it doesn’t look like it’s been a problem in the past 36 years, but since we have the opportunity to make it better, why not?  So we’ve decided to move the breaker panel from under the companionway steps to the nav station.  We ordered a Blue Sea System AC Main plus 6 Positions/DC Main plus 18 Positions.

UPDATE: March February 2017

We finally installed the Blue Sea Systems breaker panel. We moved the breaker panel from under the companionway steps to the navigation station. Rich built a nice teak frame with black ABS plastic backing for it. There’s also room for some other gauges like a Raymarine i70s Multifunction Instrument Display, the bilge pump switch and maybe the VHF radio. The AC system is switched over completely to the new panel. The DC system is still in progress. We made a couple videos about what we did and they’re linked here and here.

Engine Gauges

Rich and I argued about where to write about the engine gauges.  I wanted to put them on the Perkins page, but he want them on the Electrical page so here they are.  All the photos of the engine gauge wiring and installation are in the photo album linked at the top of this page.  You can read about what we installed here.

Navigation Lights

The original red and green bow lights on Ramble On do not meet Coast Guard regulations for a boat of our size of 2 nm (they only reach 1 nm).  We ordered LED red and green lights from Marine Beam along with a tri-color/anchor combo masthead light, a stern light, and a combination steaming and deck light.  We ran new wires through a tiny tube that runs through the stern rail.  The bow pulpit also has a tiny tube for the wires, and we’ll have to run new wire through it as well.

During the installation of the steaming/deck light and found the wires run down from the top of the mast to the deck where they’re joined in a junction block, then they go to the bottom of the compression post into the bilge to another junction block.  From there they go to the breaker panel.  So there is no way to run new or additional wires up the mast until we unstep the thing.  Boo.

To be continued…

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