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Converting a two 30amp boat to a 50amp+30amp boat. More importantly, WHY?

Calypso was built with a two 30amp AC power system. When we hooked up to dock power, we would plug two 30amp cables into it's own outlet. Each cable fed 30amps of AC power into it's own Bus which drove components. The components on each Bus were as follows:

Bus A (30amp cable 1)

  • Main House Battery Charger

  • Main Salon Air Conditioner

  • Starboard Hot Water Heater

  • Microwave

  • Washer/Dryer

Bus B (30amp cable 2)

  • AC Outlets

  • Port room Air Conditioner

  • Starboard room Air Conditoner

  • Port Hot water heater

Both Bus A and Bus B are limited to 30 amps in this configuration. If you try to pull more than 30amps on one, you'll pop a circuit breaker. Each component on the Bus will pull a specific amount of amps...10amps for a water heater, 18amps for a battery charger, etc...Total them up to over 30amp at one time and POP...The breaker pops.

While Bus B worked just fine (those AC's are smaller and the system in general never had to pull more then 30 amps). However, Bus A always seemed to be a problem.

We noticed this issue before we purchased Calypso. We were helping John, the previous owner, take Calypso to the west side of Florida to get her engines replaced. On the way back we stopped at Bahia Mar Marina in Fort Lauderdale. It was hot outside, we couldn't wait to get some air conditioning after being out at anchor for so long in the heat. When we applied power, we also tried to switch on the main air conditioner. That quickly resulted in a popped circuit breaker for Bus A. The problem was when the battery charger was in Bulk Mode (sending a lot of power to the undercharged house battery bank) , it pulled 18 amps. Turning the main air conditioner on caused Bus A to pull more than the 30amp limit. This issue happened a LOT. Over the years we had to get pretty good at managing the power for Bus A. Need to microwave something? Turn off the air conditioner first. Is the dryer and AC running, no hot water heater then unless you switch something off. The list went on and on.

When we decided to upgrade our charging system, this was a big item that we wanted changed. We knew that it was possible thanks to another Antares named Mira. They had previously completed a massive charging system upgrade to their boat, we wanted the same type of system. So we presented the issue to Dave at Marine Craft in Merritt, North Carolina who went to work designing a system to meet a huge list of requests, including this one.

"We don't want to be limited on power anymore and we're tired of the breaker popping everytime we do anything."

The system that Dave designed is robust. We'll get into specifics for each part of the system on later blog posts but let's talk about this cable configuration.

We converted Calypso from having two 30 amp inputs to a single 50amp and a single 30amp cable.

See the orange 30amp and the new white 50amp cable input below.

Here's what each do.

50amp Cable:

  • Feeds directly into three new Victron Multiplus 3000 inverter/chargers connected together to make 9000W of power. The end.

Victron Multiplus 3000's.

30amp Cable:

  • Feeds three newly installed Victron Pheonix Smart Chargers.

Three Victron Phoenix Battery Chargers.

No longer does each power cable feed a single Bus directly. The entire boat now runs off of house battery power, and I mean everything (post coming on that). So what does the the 50amp cable do?

  • The 50amp cable supplys power directly to the three Victron Multiplus 3000's (photo above) connected together to make 9000W of power. These 3000's are constantly keeping the house batterys full and inverting that power so you can use anything you want oboard. We now have the ability to run all three AC's, both hot water makers, washer/dryer and heat something up in the microwave at the same time. It's amazing. This is the only power cable we really need to run the boat while on dock power.

How about the 30amp? What's the point there? Well, we can use it if we want...Here's how and why we would:

  • The 30amp feeds power to the new Pheonix Smart Chargers (photo above) which are charging the house bank as well. These chargers do a couple of things. One, if we want to give the 50amp and Multiplus's some help, these will do that. They'll help provide power to charge the massive 1320ah Victron Lithium Battery house bank (more on those batteries later)

  • But also (and really why we decided to go this route), we can attatch an adapter to the 30amp outlet and feed 220v power (European power) right into these chargers which will convert that power to 120v standard power (which is what Calypso runs off of), they'll charge the house bank. So we no longer need to carry a heavy transformer aboard Calypso for when we stay at docks with Eurpoean power. The charging system will convert it automatically.

There are a few ways to go about accepting 220v, we chose this route because it's lightweight, and it will also help eliminate a hertz issue that we had when using the transformer. Some of our appliances didn't work because the transformer didn't convert the hertz. These pheonix chargers will. Admittedly, we will be a little underpowered while on a European dock as these will be our only chargers (the 3000's only run off the 50amp) but as long as we manage our power consumption and use our solar to help out, we will be fine.

Overall, we absolutely love being able to use the power system freely, not worrying about popping breakers or about how many amps we're pulling at once. We also enjoy only having to hook up one power cable (the 50amp) as well as the ability to add a little more power with the optional 30amp cable.

We've been doing this full-time boating thing for almost 10 years. Finding a capable, reliable technician to work on your boat is almost impossible. The industry is filled with lazy, unreliable and sleezy people, unfortunately. Sometimes you can't even get them to come take your money! Or on the other side of that, they want an absolute fortune for the work. It's absurd.

Jeremiah does almost all of our maintenance aboard to save costs but when it comes to major electrical work, he doesn't feel confident with it. So we chose to hire a professional. We chose Dave at Marine Craft out of North Carolina for this install due to many reasons. He's familiar with the boat as he's an Antares owner himself, he's professional and he knows his sh*t. When we were in the planning stages, he would take the time to email huge amounts of detail, options we had, etc. He was so detailed, in fact, that we felt bad for his taking so much of his time up without any compensation. He drove from North Carolina to Florida to do a consult and then completely relocated himself and his crew (thanks Jim and Jesse) to Florida for the two weeks this job took to complete. Once here, he didn't stop. He and his crew were probably the most professional crew we've seen aboard Calypso, we couldn't be more pleased with their work.

Thanks for reading, stay tuned for posts explaining more about this brand new power system!

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