Converting A/C system to US from Singapore

Hi,

A Transformer will change your voltage but won't do anything for your frequency.

Remember when dropping to half the Voltage you will have twice the current for the same size consumer so you will need to rewire some circuits at least.

geriksen, you say that Sea Ray did the mods at the factory?

In my experience with a largish boat manufacturer in Miami, a boat would be coming down the assembly line and a change order came through as the boat was now being sold in Europe.
Not a big deal. Some electrical pokery-jiggery was performed, and the TV was omitted (no PAL sets in the U.S.) along with changing the microwave oven for one with a mechanical timer.
Reefer compressors and the like are mostly 50/60 Hz. Likely, the A/C raw water pump is the ubiquitous Shurflo 220 VAC model.

Good advice: call Sea Ray and ask exactly what they did & how to revert to U.S.-spec.

"I would also plan on keeping as many items 220v as possible for efficiency. That boat could probably run on one 50amp 220 cord but might be better off with one 50/220 and one 50/110 as I have seen on other larger Sea Rays in the area."

Euro spec 220v (assuming that's what they use in singapore) is very different from US 220v: it has 220v between one hot and neutral whereas US 220 uses two 110v hots on opposing phase. they are incompatible systems.

In my experience it is often more cost effective, if there is sufficient space of course, to install a small shore converter. Most modern electronics will work on either 120/240 50/60hz, and motors as well. the A/C compressors, you should check the manaufacture name plate.

As far as the generator, a speed adjustment is only half the battle. Most likely the stator will need reconfigured for 240/120, as Pascal states thats two phases and one neutral and one ground, 4 wire, so likely a replacement of the feeder cable to distribution boards.

Shore power also would be three wire 240, 2 phases and one ground from the dock and a nuetral will be created on the secondary, so thats four wire from the transformer to the distibution panel or wherever the source is selected.

Reconfigure distribution boards to accept 240/120 to have two busses and one neutral bar that will be grounded. if equipment is to be changed to 120v it will need to be split up in order to balance the load between the two phases as well.

This can become quite extensive and expensive which is why i suggest a small 12-15kva shorepower unit for about $15k.

Which means if the wire is the correct size for 110v (which I'd bet it is, since I can't imagine Searay rewiring just that boat for Euro AC) you won't have to run new wire.

The purpouse of the convertor is the equipment on board will stay the same. No modifacations at all because the vessel will still be 220v 50hz single phase. being one hot one neutral and one ground. The only problem will arise if the owner decides to say replace the microwave or install a flat screen tv. But as i said most electronics now adays will operate on 100 to 240v 50/60 hz. like your cell phone or laptop charger.

it's been a while but i'm pretty sure that black is neutral in europe... ground is green with a yellowish stripe so that's no problem.

"Any 220 equipment that has a 50/60z switch or alternate wiring scheme should work on the US 220 I would think."

I dont' think so. Euro 220v equipment is powered with 220v on the hot... the US 220 power you will hook up to the boat will bring 110v on one hot and 110v on the second wire...

euro:

220
Neutral
Ground

US:
110
110
Ground

VERY different animals!

years ago when i built my house on St Barths, I wired it for both US 120 and the local 220. dual outlets everywhere and a 5KVA transformer behind the panel to convert on 220v feed to 110. that was easy... the tricky part was to use a US 220V appliance like a cloth dryer... had to use TWO transformer to convert two 220v hots to two 120v hots to power the dryer.

Color coding will not be an issue. install some electrical tape or heat shrink of the correct color and you will comply with ABYC. Take a Cheoy Lee for example, they use all yellow or orange wire??? Its fun tracing that stuff. As long as you are sure you have your hots and neutrals identified and terminated in a safe manner there will be no issues.

FYI euro colors are typicaly Black- hot, Blue - neutral, Brown- ground. but i have seen it backwards were Black was ground and Brown was the hot leg. and that was on the same Feadship. It all depends on the technician, which is why it is wise to always use your voltmeter to double check.

Pascal, i agree, it is the safest practice to use a green/yellow striped conductor for the ground. That way there is no doubt. cable manufactures use different color codes, so it depends on what the builder has purchased.

Hi,

For those posting here TessLLC is name of a very well known and respected Marine Electrical business in Ft Lauderdale.

I have personally known and done business with the Owner for over 25 yrs, he is second to none in the business in my opinion and has been of great help to me in my career as a Marine Engineer when the invisible stuff ( electricity) was causing me problems that I couldn't nut out.

Carl, If this is seen as too much of a commercial plug please delete it.

I will introduce you to the guy at FLIBS anyway.

K1W1,

Thanks for the kind words, but as always our actions and quality speak louder then words. We are all in this together and are always available to help each other out. I can only hope that whatever advice I can offer will help a brother out. I look forward to becoming more involved with YF.

Tess has not mentioned his business, nor promoted it. You simply endorsed him. He has provided relevant information that adds to the collective knowledge base. Welcome Tess.

Look forward to it!

I too have worked with Tess electric on a few boats and they do great work.