Why 220V?

[steelydon]

Its been a while since I've posted anything and it's clear nobody missed me. I bought a 2008 Ocean Alexander 48e June 2022 and sold my beloved Eagle 40 to a couple in Green Cove Springs Florida. She has a really good home now!

Yes I bought at the absolute top of the market, maybe even a little higher. Maybe I'll post about the trip home later.

My question is this. The boat has 50A service with 110/220. The water heater and cooktop are 110. The only accessory wired 220 is the AC. 3 16K units and 2 circulating pumps. The Eagle had 2 16K and 1 12K that a 6KW NL handled with no load management. What is the advantage of 220V on the AC units?

Inquiring minds want to know.

Don

 

[High Wire]

Simply the current flow will be half of that in the hot legs than the 120v versions. Wiring can be smaller and the air conditioner amps pretty much equally divided between the two hot legs. The exceptions are usually the blowers and sea water pumps powered by 120v.

 

[Delta Riverat]

Yup, more voltage allows more power. I wish my boat was wired for 230/115 with a split panel the way houses are wired.

 

[tiltrider1]

More voltage is not more power. More watts is more power. You can put more power through the same size wire with 220v vs 110v.

There are some advantages to split phase 220v if higher HP motors are needed. In general in the boating world most people use 50a 120/250v which gives them 100 amps of 110v power. Some equipment on larger boats is 220v such as clothes dryers. Most air conditioning in the marine world is 110v but some can be 220v.

Europe uses 220v and it is possible that the OP was asking about single phase 220v vs North American 110v power in which case my response doesn’t really relate.

 

[TBill36]

Don't worry about buying at the top of the market. I just knowingly (although I'm not good at predicting such things) did the same thing in March of this year. Could have waited a year or at least until the end of the summer and probably saved 20%. Had the best summer so far with the kids and grandkids that waiting can't buy.

 

[O C Diver]

So motors and compressors may be more efficient on 220 volts (consume less energy for the same output). Some motors and compressors have a lower amperage surge on 220 volts. The start up surge of the compressor is the hardest part for the generator. Finally, with each 220 volt air conditioner, the startup load is shared evenly between the two positive leads. With a 120 volt air conditioner, all the load is on one positive lead which taxes the generator that more, especially if the other loads are unbalanced between the two positive leads.

Some loads such as heating elements aren't more efficient on 220 volts. A water heater consumes the same amount of killowatts for the same wattage heating element regardless of voltage. The advantage of a 220 volt water heater is generally a faster heating of the water because of its higher wattage element.

Ted

 

[Delta Riverat]

Yeah, with a given size of wire (amp limit) you can get twice the power with twice the voltage.

 

[Peter B]

As an aside, but it is relevant to the OP's query, so not really a thread hijack, I have often wondered why the US persists in the 110v AC power grid, instead of going up to the 220-240v grid like most of the rest of the world. As it's a bit of an orphan in that respect. (A bit like your persistence in using ºF instead of ºC.)

I would think that because all your existing grid and domestic wiring is more heavy duty than required for the higher voltage - counter-intuitive though that at first sounds, but it's all to do with current - it would not therefore need extensive re-wiring anywhere. In other words, in theory at least, your grid could handle 220-240v without even breathing hard. I'm sure there will be all sorts of reasons, but it might be interesting to hear them.

 

[Delta Riverat]

We have 230 volts here, we just split it to 115 for outlets.

All the big stuff (clothes dryers, ovens and ranges, central AC units) are all 230 volt.

But yeah, the little stuff is 115.

 

[tiltrider1]

We have 230 volts here, we just split it to 115 for outlets.

All the big stuff (clothes dryers, ovens and ranges, central AC units) are all 230 volt.

But yeah, the little stuff is 115.

This is not really accurate. Our 220v is really two 110v out of phase with each other. The rest of the world is single phase 220v.

 

[Delta Riverat]

Well you get 230 VAC single phase between the "2 hots" eh?

And 115 to neutral and ground.

 

[nicklee]

Longer service life and higher efficiency

 

[psneeld]

It's only dropped to 110 at the transformers right outside your house in the US.

The lines coming into many neighborhoods are well over 10,000 volts.... that's why when they are down, they dance around and turn the ground into glass.

My guess is the reason we don't change is the changeover in appliances...sorta like boats being 12V versus higher voltages. Good idea but hard to find 24V and up stuff much of the time (less so for diesel parts because of trucking/commercial marine type parts)

The usual reason given is too costly to change out all the residential transformers, but as tech changes, not sure that would be the stand alone reason.

 

[Choices]

Europe uses 220 because they very early on realized their grid was inadequate for expansion.

So they bumped control voltage to 220, and their low voltage power from 380 to 690.

Most appliance motors, light switches, etc. can handle 220 no problem. The jump to 690 was a problem, but you had to bite that bullet to expand your plant.

Their low and high voltage transmission is all over the place.

So if you buy a European spec boat, it can be modified to US spec, and your going to learn alot about electricity in the process.

 

[sunchaser]

Well Peter you’ve got to love Canada. Up here it is 110 volt (or so) and degrees C. Since degrees C is and odd ball for all sorts of uses (it has nothing to do with the metric system) many thermostats are degrees C to a tenth.

As to 240 vs 120 volt, that argument started 130 years ago between Edison, Tesla and Dolivo from Germany. Frequencies were argued with 60 proving more efficient but with 230 volt lines using less copper. At that time the price and scarcity of copper was the main reason Europe settled on 230 volt. Oh, the Edison light bulb couldn’t survive above 110.

Japan is 100 volts and mostly 50Hz. Go figure.

But no worries Peter, Australia way back then was still focused on candle power as a measurement and sperm oil for lanterns.

 

[twistedtree]

The North American system is just way too entrenched to change. And it’s not just about the voltage, it’s as much or more about split phase vs single phase. That said, all commercial operations are three phase which is the same throughout the world, with only 50/60hz varying.

As for the Metric system, don’t get me started. We pussied out on changing back in the 70’s because the car companies whined and whined that it was going to kill them. But it turns out they were killing themselves all on their own. And now that entire industry is all metric. All the car companies, Deere, caterpillar, etc. But we continue to hang on as a country, us and Bangladesh.

 

[sunchaser]

Actually TT, the US did change unofficially to metric but as you note kicking and screaming by non technical people but over five decades ago for engineers and designers in heavy industry. The bigger problem heavy builders face are design standards for things like I beams, nuts, bolts, steel plate, rail, rebar etc. All of these areas are manageable but require extra eyes during the design, MOC selection, purchasing and receiving phases; many extra eyes.

Then comes currency confusion. The metric standard pales in comparison to doing international trade in different currencies. Not to mention the price of gold as measured by Troy ounce or diamonds in carats.

I did note that when crossing from Canada to the US yesterday my F 150s speedometer auto adjusted.

 

[diver dave]

As an aside, but it is relevant to the OP's query, so not really a thread hijack, I have often wondered why the US persists in the 110v AC power grid, instead of going up to the 220-240v grid like most of the rest of the world.

….

[emoji782]

Shock safety. If u double the voltage, the power quadruples to a fixed load.

If that load contains your heart, bad things will happen easier. Euro wiring is usually more “touch safe” than US to counter this. Both industrial wiring and residential.

 

[steelydon]

I appreciate the replies and while it does appear that there is a slight advantage to be gained by using smaller gauge wire a 110v 16K BTU unit puts out the same as a 220V 16K BTU unit. The 220v pumps and units are more expensive and less available than than the 110v units. In my case I have a 13.5KW Onan generator which is is overkill for my application.

My setup requires 2 raw water pumps and when I was taking the boat from Ft Lauderdale to NC last summer we lost one of the pumps that served two units and several calls to suppliers close enough for us to duck in and purchase revealed plenty of 110V pumps but no 220V. Uncomfortable for me and one crew member while the old man whom I had given the main cabin to in deference to his age got up all five mornings complaining about sleeping cold.

It appears I am stuck with 220V since the only option would be to replace all components adding to the high price already paid.

Don

Don

 

[KnotYet]

I appreciate the replies and while it does appear that there is a slight advantage to be gained by using smaller gauge wire a 110v 16K BTU unit puts out the same as a 220V 16K BTU unit. The 220v pumps and units are more expensive and less available than than the 110v units. In my case I have a 13.5KW Onan generator which is is overkill for my application.

My setup requires 2 raw water pumps and when I was taking the boat from Ft Lauderdale to NC last summer we lost one of the pumps that served two units and several calls to suppliers close enough for us to duck in and purchase revealed plenty of 110V pumps but no 220V. Uncomfortable for me and one crew member while the old man whom I had given the main cabin to in deference to his age got up all five mornings complaining about sleeping cold.

It appears I am stuck with 220V since the only option would be to replace all components adding to the high price already paid.

Don

You may not want to 'roll your own' solution to your specific problem but this:

https://www.walmart.com/ip/Simran-T...Power-Conversion-200-Watt-by-Simran/617200380

is a ready-made and inexpensive step-down transformer for light loads like small
pumps, etc.

 

[twistedtree]

In the context of a boat, 240V service is all about getting more power in the boat, and to various appliances. A 120V shore connection is limited to 3600W vs 12,000 for 240V service. On boats bigger than around ‘45, it gets pretty hard to power a sufficiently large HVAC system with 120V

 

[Trawlerman]

You have had many good answers, so here is a little more to think about. First of all, the typical choices at marinas here in the USA is either 120V/30 Amp sockets or the 120/240V 50 Amp sockets. If you use two 30 amp sockets you only have two times 120 Volts * 30 Amps = 7,200 watts of available load power. In the 120/240V 50 Amp socket you can have two times 120 volts * 50 amps or 12,000 watts of available load power. In addition, as a nice extra, you can run systems that need 240 volts. I have nothing on my boat that needs 240 volts, but I have enough 120 volts "stuff" that I sure do need the extra wattage capability. Just as a final PS, the days of speaking about 110 volt power are LONG gone.

 

[diver dave]

…

Just as a final PS, the days of speaking about 110 volt power are LONG gone.

Thanks for bringing that up. When i hear 110 and 220, i am reminded of my grandad.
US is 240/120.
The 220 and 240 folks in UK/continental Europe agreed to meet in the middle—230V.

 

[Circumnavigator]

.... First of all, the typical choices at marinas here in the USA is either 120V/30 Amp sockets or the 120/240V 50 Amp sockets....

Some boats, including Morning Light, have a shore power inlet for 120/50. You plug into the marina's 120/240 50 outlet, but use only one side of the circuit. In most transient marinas you pay for twice the power you're getting, but I have negotiated a lower price in all of my home marinas.

.... Finally, with each 220 volt air conditioner, the startup load is shared evenly between the two positive leads. With a 120 volt air conditioner, all the load is on one positive lead which taxes the generator that more, especially if the other loads are unbalanced between the two positive leads....

Ted

On a boat that does not use 240VAC, the generator can be wired for 120VAC -- the two 120 coils are run in parallel instead of in series, so you get the full power of the generator on one 120VAC circuit.





Jim

 

[luna]

Some boats, including Morning Light, have a shore power inlet for 120/50. You plug into the marina's 120/240 50 outlet, but use only one side of the circuit. In most transient marinas you pay for twice the power you're getting, but I have negotiated a lower price in all of my home marinas.


Although the 120/50 male might fit into the dockside 120/240 50 outlet, unless you have wired a dedicated cord for this condition, rewired the pedestal mounted outlet (likely illegal) or you use an adaptor that again has to wired differently, it would be unsafe or deadly.

The safety ground connection on the 120/240 50 outlets is on the barrel, not the prong. The 120/50 male has no connection for the ground on the barrel.

In effect, unless you have done something magical, you leave the ground behind! Not a good idea.

 

[Circumnavigator]

Although the 120/50 male might fit into the dockside 120/240 50 outlet, unless you have wired a dedicated cord for this condition, rewired the pedestal mounted outlet (likely illegal) or you use an adaptor that again has to wired differently, it would be unsafe or deadly.

The safety ground connection on the 120/240 50 outlets is on the barrel, not the prong. The 120/50 male has no connection for the ground on the barrel.

In effect, unless you have done something magical, you leave the ground behind! Not a good idea.

No magic involved. The cable has a standard 120/240 - 50 plug on the shore end, but only three wires -- green, white, and black. It leaves the red (the other hot wire) behind. The boat end has a 120 - 50 socket. See, for example, Marinco CS503-25 for which Google shows more than a dozen vendors.


Jim

 

[ronobrien]

So motors and compressors may be more efficient on 220 volts (consume less energy for the same output). Some motors and compressors have a lower amperage surge on 220 volts. The start up surge of the compressor is the hardest part for the generator. Finally, with each 220 volt air conditioner, the startup load is shared evenly between the two positive leads. With a 120 volt air conditioner, all the load is on one positive lead which taxes the generator that more, especially if the other loads are unbalanced between the two positive leads.

Some loads such as heating elements aren't more efficient on 220 volts. A water heater consumes the same amount of killowatts for the same wattage heating element regardless of voltage. The advantage of a 220 volt water heater is generally a faster heating of the water because of its higher wattage element.

Ted

The opening sentence is misleading. Everything electrical is based on wattage. Wattage is the total power consumed. Volts X Amps = Wattage So a motor that consumes 1200 watts needs 10 amps at 120 volts (forget power factor). The same motor needs 5 amps on each leg at 240 volts. So you can run smaller wiring to handle 5 amps vs 10 amps. In the end the wattage and energy consumed is the same. There is also an advantage of balance. Running a device on 220V balances the load between the 2 hot legs so that one leg isn't saturated if all your loads or all the loads for all the boats in the marina are on one leg. Understand that this is simplified. There are many contributing factors ( power factor, current leading) which is for the engineers.

 

[O C Diver]

The opening sentence is misleading. Everything electrical is based on wattage. Wattage is the total power consumed. Volts X Amps = Wattage So a motor that consumes 1200 watts needs 10 amps at 120 volts (forget power factor). The same motor needs 5 amps on each leg at 240 volts. So you can run smaller wiring to handle 5 amps vs 10 amps. In the end the wattage and energy consumed is the same. There is also an advantage of balance. Running a device on 220V balances the load between the 2 hot legs so that one leg isn't saturated if all your loads or all the loads for all the boats in the marina are on one leg. Understand that this is simplified. There are many contributing factors ( power factor, current leading) which is for the engineers.

The first sentence wasn't in reference to the same motor or compressor ( most air conditioners in the USA aren't switchable from 120 to 220 volts). If you select a unit designed to run on 220 volts, it's often more efficient than a unit designed to run on 120 volts.

Like wise, electric motors designed to run on 3 phase 220 volts are often more efficient than single phase 220 or 120 volt motors.

Ted

 

[ronobrien]

The first sentence wasn't in reference to the same motor or compressor ( most air conditioners in the USA aren't switchable from 120 to 220 volts). If you select a unit designed to run on 220 volts, it's often more efficient than a unit designed to run on 120 volts.

Like wise, electric motors designed to run on 3 phase 220 volts are often more efficient than single phase 220 or 120 volt motors.

Ted

If you re-read the part in parenthesis it says "less energy consumed for the same output". That is incorrect. You only get out what you put in (Wattage) minus heat and mechanical losses.

 

[luna]

My screen shows that Marinco's part number CS503-25 is a 125V 50 Amp 25' long cordset. To use it safely in a 125/250 50 Amp outlet you would have to first remove the original male plug and install a new 125/250 50 Amp male plug, wiring it up appropriately.

Perhaps what you meant to say was to use Marinco's adapter P504-503 or 123A, both of which would work.