220 vs 110 Volts...

[smac999]

Originally Posted by kish

The original poster alphabravo2 asked about 110 to 230 volt conversion
while you're plugged into shore power.

The most efficient solution while on shore power is to use the shore power available in the most energy efficient and cost effective manner.

There is no doubt that a conversion from the local marina's AC suopply to boats voltage system [230 to 110 volt], as described by ka4wja is the most energy efficient and least disruptive to the boats systems.

A very large battery charger to power a very large inverter, loses at both stages of energy conversion. [230volt AC to 12v DC and 12v DC to 110volt AC] is inherently more lossy than a straight conversion from 230/110 v using an isolation transformer. There is also the question of potentially shortening the life of the batteries with the large current flow.

Use of shore power from a suitably rated isolation transformer is much more co$t effective and provides galvanic isolation as a bonus.

a $10,000 atlas system is not cost effective. a transformer by itself is useless. you end up at the wrong freq. the most cost effect way to provide 120v 60hz from 230v 50hz shore power is the large charger / large inverter way. (which is basically what's inside an atlas anyways)

who wants 120v 50hz going to their north American appliances and outlets? I would call that highly disruptive to the boats systems.

[RaymondR]

If your boat is already set up with solar charging, batteries and an inverter to power all your AC devices the least cost to you will be a 240V battery charger of a reasonable capacity. Since you can leave it on all the time it does not need to have a large capacity as your batteries can carry the large, short term loads such as microwaves, and the charger will carry over and recharge through the night. Unless you want to run all sorts of heavy AC loads such as air conditioning your power usage should not be much more than when you are out cruising.

[dlymn]

If you step down to 110v, you'll probably want to replace all powerpoints as they will be European. I would check with the manufacturer to find out if they actually do change wire diameters for the Us targeted boats. maybe they wire the all the same. Undersize wire is risky and the loom is very very difficult to replace.

[Jim Cate]

Originally Posted by dlymn

If you step down to 110v, you'll probably want to replace all powerpoints as they will be European. I would check with the manufacturer to find out if they actually do change wire diameters for the Us targeted boats. maybe they wire the all the same. Undersize wire is risky and the loom is very very difficult to replace.

As I believe someone said upthread, IF you do not change t he rating of the fuses or circuit breakers, t he wire will be just fine. You may not be able to run high current appliances, but the breakers will protect the wiring against overheating. There is NO additional risk involved.

Jim

[Dockhead]

Originally Posted by Jim Cate

As I believe someone said upthread, IF you do not change t he rating of the fuses or circuit breakers, t he wire will be just fine. You may not be able to run high current appliances, but the breakers will protect the wiring against overheating. There is NO additional risk involved.

Jim

This is true.

But a 6 amp circuit which previously gave 1.6 Kw of power now only gives 800 watts. I'm guessing this will be very unsatisfactory for most people.

Sent from my SGP521 using Cruisers Sailing Forum mobile app

[DotDun]

Originally Posted by Dockhead

This is true.

But a 6 amp circuit which previously gave 1.6 Kw of power now only gives 800 watts. I'm guessing this will be very unsatisfactory for most people.

Sent from my SGP521 using Cruisers Sailing Forum mobile app

I have not seen an EU wired boat with branch receptacle circuits this small, have you?

My guess is that is not the norm with any boat built in the last 15 years.

[valhalla360]

Originally Posted by DotDun

I have not seen an EU wired boat with branch receptacle circuits this small, have you?

My guess is that is not the norm with any boat built in the last 15 years.

Would they really put in breakers for circuits equal to the max amperage of the inlet?

In the US, a 30amp boat will typically have 10-15amp breakers for most circuits (air/con being a possible exception).

We are still new the euro cruising but 16amps seems the common shore power for smaller cruising boats (sub 40'). Are they really going to put in 4-5 16amp circuits?

[Dockhead]

Originally Posted by DotDun

I have not seen an EU wired boat with branch receptacle circuits this small, have you?

My guess is that is not the norm with any boat built in the last 15 years.

I don't know. My boat is UK built and so doesn't have branch circuits at all -- it has a ring main. A bizarre idea for a non-Brit.

The point was illustrative -- whatever power you had before in any given circuit, you have half if you do what was suggested. Maybe some boat has such reserves of capacity that this won't matter, but I doubt that there will be many like that.

A lot of boats, including mine, have a lot of fixed installed AC gear and not just things you plug in. The gear will have to be replaced and in most cases the circuits will have to be rewired.

It's a pretty big PITA, which is why many boats don't bother with this, instead running 230v gear off the inverter, installing a separate 110v system with separate shore inlet, battery charger, and outlets (without removing the 230v outlets). I reckon that's what I would do. The result is that the boat is capable of sailing anywhere, and going back and forth between different voltages without any big problem.

[DotDun]

Originally Posted by valhalla360

Would they really put in breakers for circuits equal to the max amperage of the inlet?

In the US, a 30amp boat will typically have 10-15amp breakers for most circuits (air/con being a possible exception).

We are still new the euro cruising but 16amps seems the common shore power for smaller cruising boats (sub 40'). Are they really going to put in 4-5 16amp circuits?

My boat came with (2) 16a & (2) 10a branch circuits with a 16a shorepower.

Converted shorepower to 50a 240/120v, added (2) 32a circuits for AC and (1) 16a for an additional receptacle circuit. Feeding the isolation transformer with 240v shorepower, output is 120v only protected with a 50a breaker. No 240v appliances. I carry an EU 16a plug to US 50a 240/120v adapter. My charger & ACs all handle 50hz, the water heater couldn't care less.