Converting 120v/60hz to 240v/50hz

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Grae

Veteran Member
Joined
Feb 3, 2015
Messages
99
Location
New Zealand
Vessel Name
Nordic Blue
Vessel Make
Nimbus 380 Commander
Having looked at several historic threads regarding conversion of European Voltage/Hz to US I may have a very small amount of knowledge?!
All part of the learning process before committing to the purchase and import of an American trawler.
We would need to do the reverse and convert to Australian/New Zealand 240v/50Hz. Similar to Europe.

Hopefully someone can correct my assumptions as follows:
1) We would have the heavier US wiring so no problem there.
2) Switchboard/breakers 10amps (up to 2400W) so OK?
3) We would need to remove any 120v/60Hz appliances including aircon (some will work with either system as do (say) battery chargers ).
4) Install a new 240v/50hz inverter/charger
5) Remove or replace any AC power outlets with Aus/NZ 3 pin sockets.
6) Replace USA generator?
7) As most on-board equipment operates on 12 volt maybe this is no "biggy"?

Maybe "BruceK" or "Insequent" in Australia can help?
Thanks all.
 
Reduced RPM on Generator may work.
 
Some companies make transformers that are isolation transformers as well as voltage matching.

These are usually for larger boats , but a modest size should exist.

Simply plug the dock or gen set into it and have it match what the boat was built to use.

Try Mastervolt?
 
I think you have a pretty good list. As others have said, the generator can most likely be converted.

Other considerations are:

- North American power is 120V/240V split phase where the rest of the world is single phase. You should sort out how the boat is wired in this respect, and what will be required to make it all single phase. You will need to trace this from the show power inlets through to the load panels, from the generator through to the load panels, and from the inverter(s) through to the load panels. Pay particular attention to the neutral vs the L1 and L2 in split phase. In some cases you might be keeping the neutral as a neutral, and in other cases you might be turning the L2 into a neutral. This could be very easy, or moderately complex depending on the boat.

- Are there any isolation of balancing transformers used in the boat, and will they still be usable and/or even needed?

- What about shore power connections? At a minimum you will need to change the shore-side power cord plugs to match those used in NZ. You might also want to consider changing the inlets on the boat to whatever is used in NZ, and switching the power cords over completely. That way you can borrow power cords, etc. Also, I expect your shore power is typically 16 or 32A, right? That would mean you would use much smaller power cords than are typical in NA like our 50A cords which are huge.
 
Some companies make transformers that are isolation transformers as well as voltage matching.

These are usually for larger boats , but a modest size should exist.

Simply plug the dock or gen set into it and have it match what the boat was built to use.

Try Mastervolt?
Thanks for that.
Have just checked out on Mastervolt website and it seems the Mastervolt Mass GI 3.5 transformer would solve all the issues.
If this transformer lives up to specs the boat would then be left "as is" and operated as if in USA as the basic issue is really just shore contact. As "Twisted Tree" says just an NZ power cord to the transformer.
Any new or replacement appliances would need to be US sourced.
Does that sound too easy!?
 
I think you have a pretty good list. As others have said, the generator can most likely be converted.

Other considerations are:

- North American power is 120V/240V split phase where the rest of the world is single phase. You should sort out how the boat is wired in this respect, and what will be required to make it all single phase. You will need to trace this from the show power inlets through to the load panels, from the generator through to the load panels, and from the inverter(s) through to the load panels. Pay particular attention to the neutral vs the L1 and L2 in split phase. In some cases you might be keeping the neutral as a neutral, and in other cases you might be turning the L2 into a neutral. This could be very easy, or moderately complex depending on the boat.

- Are there any isolation of balancing transformers used in the boat, and will they still be usable and/or even needed?

- What about shore power connections? At a minimum you will need to change the shore-side power cord plugs to match those used in NZ. You might also want to consider changing the inlets on the boat to whatever is used in NZ, and switching the power cords over completely. That way you can borrow power cords, etc. Also, I expect your shore power is typically 16 or 32A, right? That would mean you would use much smaller power cords than are typical in NA like our 50A cords which are huge.
Thanks for all the info.
The "split phase" issue is beyond my limited electrical knowledge unfortunately. Maybe a local marine electrician or electrician with US experience would know.
Our 230/240v 50Hz appliances mostly come with 3 pin plugs (Phase, Neutral and earth) but some small appliances can have just the two 2 pins.
 
I believe 16 and 32amp shore supply is correct.
Of course all our chargers for Kindle, iphone, Macbook etc would just work with the conversion plugs we have used when in North America.
 
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A transformer like the Mastervolt may be tempting, but I would urge caution. The Matervolt that you referenced is only an isolation transformer. It isolates the shore power from the ships power, but it does NOT do any voltage conversion. Some isolation transformers can do voltage conversion, but NONE of them will do frequency conversion. So your boat will end up with a 120V 50hz boat.

You will still need to survey all your appliances to see if they will work on 50hz. Some will, and some won't. And you will still have to deal with your AC units. And do you really want a boat where you have to think about every appliance you bring on board and whether is will work?
 
The only hertz converter I am aware of is basically an electric motor driving a generator. 220V coming into the motor, 120/240V coming out of the gen end.Very simple/reliable but not very efficient.
 
Asea and Atlas make frequency inverters they're essentially large chargers feeding large inverters
.

Another thing you could do is install a wide input charger and a 50hz inverter and run the whole boat off that. Would probably need a bigger alternator too.
 
My understanding is all the modern transformers chop the power into tiny bits and reassemble it at the voltage and frequency desired.

No idea if this unit has selectable frequency out put , but it is OTS for most larger charter boats.


Perhaps these folk can help, http://www.shorpower.com/


Atlas supplies solid-state frequency converters from its ShorPOWER product line as a means of achieving clean and reliable onboard power from a dockside connection -- anywhere in the world. For owners of mega yachts, this worldwide power independence is achieved by installing a small, light weight ShorPOWER frequency converter on board the yacht thus assuring connection to any power offered by a marina. For marinas interested in accommodating the various power needs of its customers, regardless of their onboard electrical system configuration, the use of Docker ShorPOWER land based frequency converters is the solution.


For smaller yachts, Atlas supplies AutoPHASE™ Auto Isolation Transformers.
 
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Checked into the hertz converter seven years ago. At that time the only portable units were made for mega yachts and cost in the $100,000 US range.

Since then I have bought only devices that work on both 50/60 hertz. The exception on Bay Pelican is the Splendide washer/dryer. When we are connected to 50 hertz, I use the shore power to charge the batteries and the inverter to run the Splendide. My chargers, refrigeration, water heater and computers all operate on 50 hertz.

Bay Pelican has a 50 amp Charles Isolation transformer. It accepts European 220 volts and converts it to North American 220 volts. However, it does not change the hertz.
 
Setting aside all the conversion issues for a second, it seems to me that for convenience and simplicity, one would want their on-board power system (let's call that the native power system) to be the same as their home territory. That way you can buy appliances locally, use the local plug system, bring stuff back and forth from home, and guests can use the system with all their stuff without having to worry about hertz and volts and such things.

So if I were in the OP's shoes, I'd be looking to convert the boat's native power system to NZ standards. This of course assumes that you will keep the boat primarily in NZ (and maybe OZ). I don't think I'd want a boat where I always have to be thinking about what I'm plugging in, and how I'm going to do it.

Then the next question is whether you plan to take the boat outside of NZ/OZ such that power conversion will once again become an issue. Fortunately, you can travel pretty much anywhere in the world except North America and not have to worry about it. But if you think you will ever bring the boat back here, then temporary conversion might again become an issue.

Products like ASEA and Atlas are really meant for the traveling boat. They don't change the on-board native electrical system, but rather let you power it from any foreign source. The same is true for those using the charger + inverter trick which is just a poor-man's Atlas.

So I think the first question you need to sort out is whether long term you want a boat that has a native NZ/OZ power system. If you want that, then you need to convert per your original post. If you are OK with a boat that is natively a North American boat, but that can be plugged into NZ/OZ power, then that will take you down a different path.
 
Thanks Twist Tree and others,

I think that I have misinterpreted the capabilities of the Mastervolt Mass GI!

In the past I have been led to believe that 120v/60Hz appliances brought in to NZ by immigrants from North America had no long term transformer option. This, it seems, still applies.

So back to my original summary of actions needed.
Hopefully the "split phase" issue won't be a problem.
 
Setting aside all the conversion issues for a second, it seems to me that for convenience and simplicity, one would want their on-board power system (let's call that the native power system) to be the same as their home territory. That way you can buy appliances locally, use the local plug system, bring stuff back and forth from home, and guests can use the system with all their stuff without having to worry about hertz and volts and such things.

So if I were in the OP's shoes, I'd be looking to convert the boat's native power system to NZ standards. This of course assumes that you will keep the boat primarily in NZ (and maybe OZ). I don't think I'd want a boat where I always have to be thinking about what I'm plugging in, and how I'm going to do it.

Then the next question is whether you plan to take the boat outside of NZ/OZ such that power conversion will once again become an issue. Fortunately, you can travel pretty much anywhere in the world except North America and not have to worry about it. But if you think you will ever bring the boat back here, then temporary conversion might again become an issue.

Products like ASEA and Atlas are really meant for the traveling boat. They don't change the on-board native electrical system, but rather let you power it from any foreign source. The same is true for those using the charger + inverter trick which is just a poor-man's Atlas.

So I think the first question you need to sort out is whether long term you want a boat that has a native NZ/OZ power system. If you want that, then you need to convert per your original post. If you are OK with a boat that is natively a North American boat, but that can be plugged into NZ/OZ power, then that will take you down a different path.
The boat will stay in NZ and the complete conversion would be my far preferred option for all the reasons you quote.
The transformer possibility had been rubbished in the historic threads as well, so I wondered if it was just too simple to be true!

So after that red herring and back to my original summary it appears that along with my NZ shore connector it may be just the split phase issue to be solved?
 
So after that red herring and back to my original summary it appears that along with my NZ shore connector it may be just the split phase issue to be solved?

I think so. And the split phase thing may not be a big deal at all. But you are doing a good job of really identifying the work needed, so you might as well make it complete.

Can you tell us what make/model boat?

And do you know much about it's electrical system? For example, what are the shore power connections in number and capacity? Are there both 240V and 120V appliances on board, or just 120V? Your HVAC, water heater, and stove/oven would be top candidates for 240V service. Are there other appliances on board like washer and dryer? Water maker?
 
I think so. And the split phase thing may not be a big deal at all. But you are doing a good job of really identifying the work needed, so you might as well make it complete.

Can you tell us what make/model boat?

And do you know much about it's electrical system? For example, what are the shore power connections in number and capacity? Are there both 240V and 120V appliances on board, or just 120V? Your HVAC, water heater, and stove/oven would be top candidates for 240V service. Are there other appliances on board like washer and dryer? Water maker?
This is the long answer to your boat model question! Hopefully not too off topic.

I have started my research about 10-12 months in advance primarily to ascertain the viability of importing our preferred boat from the large "pool" of vessels in North America.

We are looking at Nordic Tug 32+ and American Tug 34 which have the configuration that we think would suit us as a retired couple wanting to live aboard while coastal cruising between the Bay of Islands and Tauranga Harbour on the Northeast coast of NZ. Low maintenance is also an attraction.

We don't want to spend much over NZ$300.000 landed which equates to sub US$200.000. A island bed is a liveability issue as well.

While the flybridge of the Mainship 34 (available here) is attractive from a live aboard perspective giving more space to spread out, it seems less of a good sea boat and the extra windage and maintenance are other issues. I have also read that most owners operate almost exclusively from the flybridge due the poor visibility from the lower helm.
Our weather isn't that predictably good!
Our present intention (could change) is to base ourselves at a central marina and coast hop North and South.
 
Sounds great. We hope to make it over there in the next couple of years. We have family in Wellington.

I don't know enough about those boats to be sure, but expect they are likely built around 1 or perhaps 2 120V, 30A shore power inlets. As such they would be all 120V with no 240V. If it's two 30A circuits, then the generator is probably set up as 240V split phase (our little North American wonder) with each half serving one of the two 30A branches. This of course is all speculation, but if it's set up that way the whole spit-phase issues should be easy to deal with.
 
I have googled some of the brands/models of fridge, freezer etc and most seem to be dual voltage. Microwave, TV etc are not so important. Most important is battery charging from shore mains power.
 
Most important is battery charging from shore mains power.

Plugged in 24/7 just 10A will work for most liveaboard purposes.

Just buy a second batt charger , and as gear fails replace it with 12v or 24v stuff to match the vessels house bank.
 
Having looked at several historic threads regarding conversion of European Voltage/Hz to US I may have a very small amount of knowledge?!

All part of the learning process before committing to the purchase and import of an American trawler.

We would need to do the reverse and convert to Australian/New Zealand 240v/50Hz. Similar to Europe.



Hopefully someone can correct my assumptions as follows:

1) We would have the heavier US wiring so no problem there.

2) Switchboard/breakers 10amps (up to 2400W) so OK?

3) We would need to remove any 120v/60Hz appliances including aircon (some will work with either system as do (say) battery chargers ).

4) Install a new 240v/50hz inverter/charger

5) Remove or replace any AC power outlets with Aus/NZ 3 pin sockets.

6) Replace USA generator?

7) As most on-board equipment operates on 12 volt maybe this is no "biggy"?



Maybe "BruceK" or "Insequent" in Australia can help?

Thanks all.


Just over a year ago my wife and I imported a Kadey Krogen 48', a 2006 model into Australia.
We discovered that most boats built after '04 would take 50 or 60Hz which was a bonus. We simply added a step down transformer which we plug in to the boat's existing 110v shore power inlet, in this case a Glendenning Cablemaster. Everything works just fine except for the clothes dryer which won't heat, or the air conditioning which we seldom use. The inverter/charger works perfectly.
We have not changed a thing, for example, phone chargers work fine on 110v. We kept all our appliances except for the LP gas oven and cooktop simply because the model fitted was not approved for use in Australia.
If we want to run the air conditioning or clothes dryer we simply run the generator. If we added a second transformer we could also run the air.

If you care to message me I can give you all the details.
 
I figured that as the easiest approach thanks for confirming.
 
It's a great help to hear from a contributor who has been through the process.
Thanks for the offer of more specific info and I would like to take you up on that a little farther down the track if that's OK? When we are closer to finding the right boat I'll be better equipped to ask the right questions. .... G
 
Other factors to consider: When you find your boat estimate the cost of converting the boat to 220 with step down transformers for expensive North American appliances you want to keep. That way as the years go by and you have to replace the appliances you can install 220 units. When you eventually sell the boat you will not have to discount her for being a North American boat in a 220v environment.

Another factor I have lived through is the availability of replacements when your boat is the different electrical system. Bay Pelican is currently in Martinique, a 220v island. There are at least 100 North American boats in this anchorage. Yet we could not replace a coffee pot, TV, DVD player, toaster etc. if we had to. Plugs and voltage are all different.

Workmen need to bring transformers aboard. Here with all the North American boats the workmen are use to the problem. Don't know if that would be true for you.
 
Grae
The owners/managers of AT I have met and talked with build their vessels for non US markets when requested. Once you settle on a specific vessel talk to the builders and they could give you some guidance on the choices for conversion. Don't forget to think safety as you go down this route.

BTW, the other thing to consider is to have the conversion done at the AT factory in Wahington it you buy your vessel there. NT may be open to doing the same. Both builders should be interested in this sort of "advertising." Having spent some time in the Bay of Islands you would find the PNW fertile cruising grounds as well before you ship the vessel.
 
Other factors to consider: When you find your boat estimate the cost of converting the boat to 220 with step down transformers for expensive North American appliances you want to keep. That way as the years go by and you have to replace the appliances you can install 220 units. When you eventually sell the boat you will not have to discount her for being a North American boat in a 220v environment.

Another factor I have lived through is the availability of replacements when your boat is the different electrical system. Bay Pelican is currently in Martinique, a 220v island. There are at least 100 North American boats in this anchorage. Yet we could not replace a coffee pot, TV, DVD player, toaster etc. if we had to. Plugs and voltage are all different.

Workmen need to bring transformers aboard. Here with all the North American boats the workmen are use to the problem. Don't know if that would be true for you.
Thanks for that. Good advice. I am certainly keeping in mind eventual resale. G
 
Grae
The owners/managers of AT I have met and talked with build their vessels for non US markets when requested. Once you settle on a specific vessel talk to the builders and they could give you some guidance on the choices for conversion. Don't forget to think safety as you go down this route.

BTW, the other thing to consider is to have the conversion done at the AT factory in Wahington it you buy your vessel there. NT may be open to doing the same. Both builders should be interested in this sort of "advertising." Having spent some time in the Bay of Islands you would find the PNW fertile cruising grounds as well before you ship the vessel.
That is very interesting. We have always been interested in PNW and would love to explore. Never been farther north than San Francisco.
One potential problem though is shipping the boat home to NZ. We are told that shipping from the west coast is very difficult compared with sourcing in Florida. We have been interested in fresh water boats from the Great Lakes but added costs of road transport apparently effectively rule out that option.
The west coast generally refers to California with no mention of any port further north. Maybe no port up there used by suitable ships?
 
That is very interesting. We have always been interested in PNW and would love to explore. Never been farther north than San Francisco.
One potential problem though is shipping the boat home to NZ. We are told that shipping from the west coast is very difficult compared with sourcing in Florida. We have been interested in fresh water boats from the Great Lakes but added costs of road transport apparently effectively rule out that option.
The west coast generally refers to California with no mention of any port further north. Maybe no port up there used by suitable ships?

This doesn't sound right.

I would think the opposite, shipping from the west coast would be preferable.

The Port of Tacoma may be the second largest port on the west coast after Long Beach.

As twisted tree and bay pelican have pointed out, I would stick to your original list, change appliances, outlets and modify generator.

But as you add new things, try to get ones that work on both 50/60 hz.

Richard
 
This doesn't sound right.

I would think the opposite, shipping from the west coast would be preferable.

The Port of Tacoma may be the second largest port on the west coast after Long Beach.

As twisted tree and bay pelican have pointed out, I would stick to your original list, change appliances, outlets and modify generator.

But as you add new things, try to get ones that work on both 50/60 hz.

Richard
One would think Long Beach would be best being just across the pacific, however any shipper we have asked has told us to forget the idea. Apparently they are basically a container port,not set up for shipping boats and/or expensive.
Thanks for confirming the general trend of advice re conversion.
 
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