Atlas FAQ

Sans Souci has a huge device sitting in the lazarette, called the Atlas. I'm not sure what it weighs, but I would guess that it is at least a thousand pounds. The Atlas can be purchased as a single unit that is about the size of a refrigerator or, as in Sans Souci, it is broken down into five distinct units, each of which with a different function. I chose the "modular" system, as the single-box system was too tall to fit in my lazarette. This picture shows two of the pieces.

What does an Atlas do?

Simply stated, an Atlas sits between the boat and shore power, and converts the shore power into something the boat can handle. If a boat is going to spend the majority of its time in the US, it probably doesn't need an Atlas unit. However, if the boat is planning on wandering from country to country, as we are, then an Atlas (or equivalent) is probably needed.

Electricity comes in different "flavors" around the world. US shore power pedestals are normally 240 volt, 60 hz, single phase. To be accurate, the pedestals normally have two single phase legs of 120 volt electricity. These two legs can be combined for 240 volt electricity, or used individually to get 120 volt electricity. As a boat moves from marina to marina around the US, the only major variance is the "amperage" of the shore power. For instance, marinas will have 15, 20, 30, 50 or 100 amp shore power. Each of these has a different connector, and most larger boats carry a collection of shore power adapters. In all of these cases, the electricity is the same, what changes is the amperage. Amperage is an indication of how much electricity can fit through the wire before you trip the shore power breaker. Think of the electricity as water flowing through a pipe. The electricity in this analogy is the water, and the amperage is the size of the pipe. A 100 amp pipe can carry more water than a 15 amp pipe. As boats get larger, you consume more electricity. This occurs because on the smallest of boats, the electricity is only being used to run the TV, and a battery charger, whereas on the big boats you have multiple refrigerators, freezers, air conditioning, and more. Really small boats are generally happy with 15 or 30 amp service, whereas big boats need 50 to 100 amp service.

There are variances in the power around the US. For instance, it is not uncommon to see 208 volt service. It is also not uncommon to see voltage vary widely within a marina. As the load at a marina increases, the voltage can start to decline. Also, some marinas have crappy wiring, and long runs out to the boats. This degrades the quality of the electricity, which can be harmful to the electronics on your boat.

Outside the US, more than just the amperage can vary. Remember I mentioned that there are three components to electricity: voltage, frequency and phasing? All of these can vary as you move around the world. Attaching your boat directly to shore power in these countries can destroy the equipment on your boat.

Outside the US, it is apparent why you need the Atlas, but there are also reasons within the US. As I mentioned earlier, the voltage in marinas is subject to fluctuation. The Atlas converts whatever voltage it finds at the dock into perfectly clean reliable electricity. It provides several other functions as well. For instance, when an electric motor starts, it consumes far more electric for an instant, than after it is running. This sudden demand can trip a shore power breaker. The Atlas can buffer this, supplying the needed current to get a motor rolling. Another benefit of the Atlas is that you can bring in multiple shore power cords. For instance, you can use two 30 amp cords, to get 60 amps. The Atlas completely isolates the power on the boat from the shore power, protecting your appliances from the uncertainty of shore power connection.

Boats have been circumnavigating for centuries without Atlas units. How?

Both power and sail boats have circumnavigated without Atlases. They have done this via a variety of techniques. Most do it by simply doing without shore power. Most boats have a generator, a battery bank and an inverter. The generator charges the batteries, the batteries supply electricity, and the inverters convert the 12 or 24 volt DC current from the batteries, into 120 or 240 volt AC current for use around the boat. Usually the batteries need charged a few hours a day. After a while this becomes a routine. Each morning you run the generator for a couple hours, then again before bedtime. When in port, you have to do the same, because you cannot attach to shore power.

There are some problems with this approach however. 1) If you are away from the boat someone needs to run the generator for you, or you need to COMPLETELY disconnect everything on the boat that consumes electricity. 2) The batteries, and the inverters, rarely have the capacity to run the larger appliances, such as washing machines, dryers and especially air conditioning. 3) Marinas don't really want you running your generators at the dock. They are noisy and smelly. And, 4) The generator consumes fuel!

On our prior Nordhavn we did something which represented a bit of a compromise. We had a battery charger, which would run off US or European electricity. By doing this, the boat was running off of the inverters, and the battery bank always stayed charged. The only limitation was that the heavy appliances consumed too much power to be run through the boat's inverters. To address this, we "hot wired" the heavy appliances to run directly from shore power. We were cruising Europe and the voltage was roughly the same, but the frequency was not; 50hz instead of 60hz. The appliance ran fine, although hotter than usual, and we burned out a dryer. Overall though, this wasn't horrible. We had limited inverter capacity and were constantly having to think about what we could power on and what we couldn't. From time to time, such as if we wanted to run a toaster, or the Microwave, we needed to start the generator in order to meet our needs.

Are there other companies besides Atlas that make shore power adapters?

Yes. There are many companies. I'm not sure whether Atlas is the best or the worst. I've been told that Atlas makes one of the best shore power converters. To see some of the other companies, enter something like "Shore power frequency converters" into Google, and you'll find them.

What problems has Sans Souci had?

Our Atlas performed flawlessly until the last month, in Mexico. For some reason, it attaches to shore power, but then shuts itself down randomly. When it quits, there is no error message or indication of a problem. It is as though someone pressed the stop button.

Because we're in Mexico, my first thought was that it was the power at the marina. Atlas walked me through doing a variety tests to isolate the Atlas, from both shore power, and from the boat. These tests seemed to indicate that the problem was inside the Atlas.

The Atlas technician walked me, over the phone, through dismantling parts of the Atlas. Nothing seemed to help. Ultimately, an Atlas technician, and a Nordhavn technician, came to the boat, and spent several days. The technician's theory was that some of the control wires linking the various Atlas modules were not making good connection. All of these wires were removed, re-stripped, and re-attached. This did seem to make things better, but didn't solve the problem. They then looked at the grounding and decided that there were some ground wires which had not been installed. The wires were installed, and the system tested. It worked! The technicians flew home, and I flew to Seattle, and four days later the system failed again. We reset it several times, and it failed several times.

Does this mean Atlas is no good?

Absolutely not! The Atlas is a fine, and much needed, unit. My particular unit is not working, but I doubt that 100% of the TVs Sony sells, or cars that General Motors sells are perfect. Sometimes a unit goes out the door that has, or develops, a problem. At this time, we still don't know what the problem is, so I can't say whether it was a problem with the Atlas, something that is a result of the boat being slammed around at sea, the result of a flawed installation, or ???

Currently, the boat is running on the generator, and I am cutting my trip to Seattle short to go "work on it." I'm not sure I can accomplish anything. This is going to require the Atlas technician coming back to the boat.

Are shore power converters unreliable?

No. I've spoken to several people, and shore power converters are extremely reliable. The Atlas technician has not seen one as stubborn as mine. I remember when I was configuring the boat asking Nordhavn's electrical guru whether or not I should install a bypass for the Atlas, in case it failed, and he said it was unnecessary; that Atlases do not fail

Would another brand have been better?

I seriously doubt it. I have no way of knowing, but would assume that every company has sold at least one system that didn't work at some time. Things break, and on a boat that is slammed often enough by heavy seas, they tend to break more often. If anything, I am happier with Atlas than I was when I purchased the unit. Many companies would have gone way out of their way to finger point. Neither Atlas, nor Nordhavn, has gotten into that. Both companies have sent technicians, who have worked well together as a team to solve my problem. Both companies have been extremely responsive, and my problem will be solved. I'm frustrated, but not blaming anyone. If I were the type to be upset by something not working, I probably shouldn't be planning on circumnavigating. Boats have redundant systems for a reason.

Should people buying a boat consider adding an Atlas?

That depends on where you are going to cruise. If your boat is going to spend the vast majority of its life in a single country, it probably isn't worth the space requirement and cost. However, if your goal is to travel the world, and you have the space, and the money, it does make life a lot more pleasant.

What would I do differently, if I had it to do over again?

I should have pushed harder for a bypass on the Atlas. It is frustrating to sit at a dock with good shore power and not be able to use it, because the Atlas has failed. Even though it is rare for an Atlas to fail, virtually every "thing" on a boat fails sooner or later. You should always have a plan for what to do should something fail. In this case, I had to leave the country and had no way to bring the power to the boat without the Atlas. I "solved" this by running the generator, which is a FAR from perfect solution. I REALLY don't like running the generator while I'm not on the boat, although it should be perfectly safe to do so.