adapting shore power

[captjohn360]

hey mates my boats shore power is wired for 240 v at 50 hz. how can i convert to 60 hz to 50 so i can use my shore power in the U S. jt

[GordMay]

Converting Euro’ 240V 50Hz AC ~to~ N/A 120V 60 Hz AC:

The conversion from a European 50Hz 240VAC system to a North American 60Hz 120 (or 120/240) VAC system may be fairly simple, or a little more complicated, depending upon the equipment connected to it.

We will need a lot more information on you current boat wiring and equippage to provide any useful specific advice on your conversion - but here’s a few generalities to get you started:

FREQUENCY:

Motors are designed to operate within a certain frequency range - and while some may be more or less universal, most will be rated either 50 Hz or 60 Hz. Motors designed to operate on 50 Hz will run faster on 60 Hz.

Electronics may or may not be input frequency sensitive (check your manual). Euro’ Televisions & Microwave Ovens will NOT work in N/A.

CONNECTIONS:
Contact me for faxed graphics @ Gord@BoatPro.zzn.com

Convenience Receptacles and Shore Power Inlets are configured differently, and all will have to be replaced. Obviously, portable devices (plug-in) will have to be replaced.

240 V European: Two “Slanted” (or horizontal) blades over Vertical ground.
“Hot” Brown
“Neutral” Blue
“Safety Ground” Green /w Yellow Stripe

120 V North American: Two “Parallel” Vertical blades over “U” ground.
Black “Hot” has 120 Volts to Neutral & Ground
White “Neutral”
Green “Safety Ground”

120/240 V North American:
Black “Hot” has 240 to “Red” Hot”, and 120 V to Neutral & Ground
Red “Hot” has 240 to “Black” Hot”, and 120 V to Neutral & Ground
White “Neutral”
Green “Safety Ground”

VOLTAGE, AMPS, & POWER:
Power (Watts) = Volts x Amps
Amps = Watts ÷ Volts
Hence
To achieve the same power output (Watts), a 120V N/A device will draw TWICE the Amperage as it’s 240V Euro’ equivalent*.
ie: a 100Watt device will draw 0.416 Amps @ 240 Volt; but 0.833 Amps @ 120 Volt.

* CAUTION:
Fuses, Circuit Breakers, and Wiring are rated in Ampere capacities - hence extreme caution is advised when converting from a 220V supply to 120V.

Converters and Transformers only change the Voltage, and not the Frequency.
Converters are typically used to decrease the AC voltage from 220V to the 110V level needed by the appliance.
Transformers are used to increase or decrease the voltage, and might be used for electronic devices such as radios, televisions, computers and other devices having electronics circuitry.

HTH,
Gord

[Alan Wheeler]

I only have two points to make. But please read and Digest Gords excellent reply.
Stepping down is easy. As in a 120V vessel going to a 240V country. A step down transformer is easy and relatively cheap to buy, and not so large in pysical size. A 240V vessel wanting to connect to 120V is a little more difficult. Step up Transformers can be obtained, but they are much larger and expensive. This is due to the currents required to be handled.
Soooo you can step up as one option. Another option however, is to use a dual voltage Switchmode P/S charging system, have a decent battery bank and an inverter. The first and latter can be one and the same unit, as an inverter/charger. Then run all your vessel via the inverter. The economics of this has to be balanced against the cost of a step up Trany, but it does solve any problems with frequency. Plus, it means you can go to any port in any country and not have to worry about voltage supply. Some countries have 220V, some 240V, and so on. For example, we are 240V =/- 10%. I was seeing darn near 260V in my Marina the other day. For 220V equipment, this can cause failure of fuses, as the current rating of the fuses is designed for a 220V calculation. It shouldn't hurt the equipment, but I do say shouldn't not won't.

[Jentine]

I would assume that while you are at sea, you operate on 12V. I would install a 12V battery charger and run everything off the same source used at sea. It is the most cost effective and requires the least amount of work.

Jim Kane

[captjohn360]

i have a refer,hot waterheater and a battery charger. not wanting to replace them $$ if ican help it thanks jt

[captjohn360]

thanks j k i do have a 12v to 240 inverter so one option i thought of was to buy a battery charger and install 110 shore power. jt

[Alan Wheeler]

If all you are worrying about is a charger and a water heater, neither should be affected by difference in line freq or minor variances in voltage supply, like 110-120V/220-240V.
I would buy a stepdown transformer capable of handling the current draw of both units. The only problem that should arrise with transformer based P/S in your appliances, is that 60Hz tranys require a smaller iron core. Running a 60Hz trany on 50Hz often makes the trany run a little hotter and a little noiser. As Gord said, motors are a different story.
The problem you may enconter with a stepdown trany is the current required for your water heater will mean the stepdown trany will need to be large. This could equate to expensive. But check around Ebay etc. There is a large one on Trademe.co.nz at the mo, so they can be found if you have patients.