AC System Upgrades

AC System Upgrades
Botany Bay's original Oyster electrical system was designed for 230V 50cycle power which at some point in her life had been "bandaided" to work with US 240V split phase power. To understand the issues with how this was accomplished and to determine the "right" path forward to end up with a safe, efficient, and hopefully simple (in operation) system which can be used with the various kinds of power found at marinas in the US as well as the rest of the world. Let's first look at the original system as designed. British power found in marinas (and European power is close) is similar to US 110V power. There are three wires, Hot (Brown), Neutral (Blue), and Ground (Green w/Yellow Stripe). Thus, like a vessel wired for US 120V 60 cycle power it is common to have double pole breakers as the first breaker after coming on the boat and then single pole breakers for the remaining circuits. The shore power connection available at a dock is often either 16 Amps or 32 Amps. Like US power systems a "galvanic isolator" is used to block current flow between the vessel safety ground and shore safety ground allowing the potential between the two grounds to reach a small value (a volt or two) prior to conducting. This ensures that if the "hot" wire were to come in contact with a conducting portion of the vessel that the breaker would trip ensuring that if the ground bus becomes energized on the boat it will not produce a dangerous situation. Next, let's look at the power forms which are commonly found in the US on boat docks: 120V @ 15A - Basically a home power outlet for marine use, not commonly seen except in very small marinas and generally older marinas 120V @ 20A - The connector looks different (connector name) but is essentially standard power from home at a higher amperage 120V @ 30A - This is the most common power found in marinas with slips between 25 and 50 feet. Like home, it is a three wire system with "hot" (Black), "Neutral" (White), and "Safety Ground" (Green) 120V @ 50A - Similar to the 30A system but with larger blades on the plug to carry more current 240V @ 50A - This is two 120V phases which are 180 degrees out of phase, the two phases are often called "L1" and "L2", the voltage between L1 and L2 is 240V, Between L1 and Neutral is 120V, L2 and Neutral is 120V. This is similar to "Electric Dryer" circuits found in many homes. About half of the US marinas which provide voltage above 120V use this system 208V @ 50A - This is two 120V phases which are 120 degrees out of phase, generally created by taking any two legs of a three phase 240V circuit. This costs less to implement, (something like $300/slip) per a comment on the internet, most hardware will run but the lower voltage is at the lower range of many "220V" tolarances. The primary issue for me is that the same plug is used for 240V and 208V! Additionally, due to the phase offset differences a 240V split phase inverter cannot connect to a 208V system and a 208V system setup for 120 degrees of phase difference cannot be connected to a 240V split phase system. In the best case the inverter will refuse to connect the power, in the worst.... So, if you leave the comfortable relm of 120V equipment and wander into the 200+ V regime you must be VERY CAREFUL, specifically, assume someday someone is going to plug the boat into the wrong form of 240V or 208V power and that bad things may happen if you don't setup the system to function with either power form. Now, back to the bandaided system I inherited from one of the previous owners of the vessel. It appears that the vessel was setup assuming that all plugs labeled "125V/250V 50Amp" are 240V split phase systems, an "autotransformer" was used to create 110V power from the 240V power which at least kept the two phases of 240V power balanced. However, while there are double pole breakers when the power comes into the primary panel and then GFCIs to look for a ground fault, the downstream circuit breakers are SINGLE POLE! Thus, with L1 connected to Neutral and L2 connected to Hot, if you turn off the breaker to a piece of equipment the neutral leg is 120V relative to safety ground or shore neutral!!! Luckily I realized this while drawing diagrams of the vessels electrical system at the time several thousand miles from the boat. Additionally, an independent 60 cycle inverter is on the boat, installed at some point in time. It appears that it was setup for 102V? Or that the equipment has failed to a point where that is the voltage it is putting out. It will run computer electronics but things like the shop vac or other motor dive hardware will not function correctly with this inverter. Additional research is needed to determine if this was by design or if something is wrong, it is a Trace 1500 Watt unit. So, if no other changes are made one could use double pole breakers for the 200+V circuits and at least make sure that when the breaker is off the equipment is not hot. However, this depends on the equipment onboard being able to handle the European "Neutral" line floating 120V with respect to safety ground. Luckily all of the hardware aboard appears to fit this requirement and the expensive systems (refrigeration and two air conditioners) specifically allow either European 230V hot/neutral and US 220V with two hot lines. An inverter capability is necessary if it is desired to run the refrigeration system off of battery power (200 - 240V capable) and a different inverter would be required to run 110V equipment like a TV etc off battery power. This is option 1. Option 2: Use a "multi tap isolation transformer" to convert 208V / 240V US 60 cycle power into a single phase running at 240V (or perhaps 230V) with neutral and ground bonded on the vessel leaving shore ground only connected to the shield of the isolation transformer. Then the single pole breakers are acceptable Option 3: Use and "multi tap isolation transformer" to convert 208V / 240V US 60 cycle power into split phase 240V with the center tap as neutral and bonded to ground on the vessel leaving shore ground only connected to the shield of the the isolation transformer. Double pole breakers would be required for 240V equipment, note that 240V equipment must allow both phases to be 120V from ground (and neutral if used) Option 4: Convert all of the AC power coming onto the boat into 24V DC (about 300A DC!) and then use inverters to make the desired power forms, either 230V 50 cycles for european equipment, 240V 60 cycle split phase for US high voltage equipment and 120V 60 cycle power for household electronics. This is not an inexpensive route but it can potentially use any power form from 90V to 260V and 40 hz to 70 hz frequency. As an interesting aside it provides for massive battery charging capacity and allows running the engine with a large alternator to backup the generator. Idling current is about 30 watts. Option 5: Use a power converter like those provided by A/Sea Systems in Huntington beach. These systems can use power from 160V to 260V between 40hz and 70 hz to make either 230V power, 240V split phase at either 50 or 60 hz. The downside is that you still need an inverter as this is an AC to AC converter, it weighs 230lbs, and it consumes 300 watts idling or about 30024=7200 watt hours/day = 7.2 KWH/day. Now, power in LA is about 19c/kwh so this costs $1.38/day, $40/month or about $500/year in increased electric bills! The cost for such a unit is in the neighborhood of $15K - $20K USD depending on capacity and features. Option 6: Convert the boat to use 240V split phase power directly, some form of galvanic isolation is still necessary, double pole breakers are required, an inverter is required to avoid having to run the generator to chill the fridge, make popcorn, etc. The boat cannot use anything but 240V split phase power... Option 7: Convert the boat to use 208V 120 degree phase power directly, some form of galvanic isolation is still necessary, double pole breakers are required, an inverter is required to avoid having to run the generator to chill the fridge, make popcorn, etc. The boat cannot use anything but 208V 120 degree phase power... Inverters to support this power form are difficult to find Option 8: Convert the boat to use each leg of the power form directly. i.e. run everything off of 120V power and treat it as two 50A circuits... This requires replacing all of the AC units, the Fridge compressor, microwave (need to replace anyway), the washer/dryter (need to replace soon), and the hot water heater element. Generator would have to be rewired to run 240V @ 35 Amp split phase power (and monitor phase imbalances carefully) or rewire to 120V @ 70A. Most of the wiring on the boat would have to be upgraded for the higher current of 120V circuits. Let's look at the cost and functionality provided by each of these options... Option 1) is the "minimum compliance" solution to get a safe system. It is most likely an intrim solution as the original circuit breaker panel is in need of replacement for many of the options and as it appears that during the deck rework by the previous owner the panel has been subjected to some level of water corrosion. The addition of the inverters starts to make this system look like one of the other options below depending on the configuration. For now let's assume $1000 to have a custom AC/DC power panel manufactured. The existing 120V 60 cycle inverter could be used to provide power to the boat directly without a shore connection or an "autotransformer" could be used to provide 120V power. If the existing 1500 watt Trace inverter can be salvaged (in question due to the 102V current output) then the total cost of a minimum compliance solution would be the cost of the power panel. The downside is that none of the 230V equipment can be powered from the inverter requiring running the generator for 1 - 2 hours/day to keep the holding plates frozen while disconnected from shore power. Additionally the vessel is still directly connected to shore ground, at minimum a galvanic isolator would be a desired improvement to limit the utilization of zinc and potentially damaging corrosion when in harbors with suspect shore power, a galvanic isolator would be about $600 for a 50A unit but an isolation transformer would be more robust but that looks more like the later options. So, this option is between $1000 and $1500 USD Option 2) This option makes the dock US power into something that looks very much like European power with the exception of being 60 cycles rather than 50 cycles. It also provides the ability to work with 110V, 208V, and 240V US power (and even overcome dock power undervoltage sags) depending on the level of automation. Galvanic isolation is provided by the transformer. Charles industries does produce such a transformer which can operate from 160V - 260V 50hz & 60hz. The 240V only version is 230lbs, is approximately 22" x 18" x 12" and costs about $1800, the automatic multitap version is the same weight and size however, the cost is almost double at $3200 for the unit. Unfortunately the transformer technology used by Charles Industries has a significant 50 or 60 cycle hum (65 dBA) which is always there if the transformer is energized. It is noted in the manual that the transformer should no be mounted under sleeping bunks or in the main cabin due to the noise level of the transformer. This transformer can support the full 50A of the shore power connection thus providing 12KVA at 240V (47A @ 240V when energized by a 240V circuit including the 5% quoted loss) or 10KVA at 208V (41A @ 240V provided when energized by a 208V circuit including the 5% quoted loss). 120V power could be provided either via an autotransformer, or provided by the Trace 1500 Watt inverter (with the current 102V output for some reason). This solution does provide galvanic isolation to the boat, provides for the correct single phase power form like a European system which would not then require replacing the breaker panel with a double pole system. If the existing 60hz inverter cannot be salvaged a new inverter for 120V power would be required to run general electronics with the generator off. The "idling power use" of this system would include the minimum energy used by the transformer (about 100 watts or about 1% of peak) and would generate about 500 watts of heat at full load. The cost of this option is about $3200 USD for major components and some additional for wiring and additional circuit breakers. I have found two other vendors which produce "high frequency toroidal isolation transformers" for marine use. Mastervolt and Victron Energy. Mastervolt's system is called the Mass GI 7.0 multi tap (manual)which can accept source power over a voltage range of 90 - 145 or 180 - 255 V AC (it is not clear if the two ranges are in the same device (hopefully) or if some jumper or something would have to be adjusted manually to switch between the two ranges. This is a 7 KVA device which can handle 32 A cont. @ 40 °C/104 °F independent of the input voltage. Thus if supplied with 208V there is 29A of 230V power available. If supplied with 120V current then approximately 16A of 240V power would be available. These devices can be paralleled to create a larger unit with double the power available if needed. The weight of each unit is 22 lbs, the size is 13.4x10.3x11” with a price per unit of 3'329.00 CHF or about $3000 USD. The question here is if two units are needed or if a single unit will suffice. I have heard some comments about these units failing if highly loaded for an extended period of time so the proper solution is to use two of these units on a 50A circuit rather than putting in a 32A circuit breaker to limit the load. Additionally, this would allow the use of two 120V 30A connections to provide 30A of 230V power to the boat or use a single 120V 50A circuit to run each transformer at 25A input providing a combined output of a 26A at 230V. These units are supposed to be very quiet and thus could be mounted in the main cabin behind the settee, The total weight would be either 22lbs for one unit or 44lbs for two units, the idling power consumed is less than 60W/unit thus less than 120W for two units. I have not found an efficiency value for the unit thus a peak thermal dissipation. This system does provide the ability to monitor everything you would want to look at with regard to history from the original startup and from the last power connection providing all of the needed information to monitor power consumption of the vessel. If you assume 7000VA @ 230V (nominal output) from 32A @ 230V input (nominal input) you get 95% efficiency or a very similar number to the normal isolation transformer. So, no thermal/power savings here and a very similar idling current. Basically, the advantages of this approach are weight, space, monitoring capability. If two units are needed the cost is almost 2x the normal isolation transformer, if one is enough then the costs are similar. See discussion below about needed power aboard. The total cost of this option is either $3000 USD or $6000 USD (not including the mastervolt control panel which is 446 CHF or about $400 USD) depending on if 7KVA is sufficient for all of the equipment on the boat. Unfortuantely as of Early 2010 this device (the Mass GI 7.0 multi tap) is vaporware, I tried to order one and was told "It is still in development". I have again pulsed them (August 2010) to see if I can get some indication of when they expect it to be available but as usual I have not managed to get Mastervolt in Europe to respond. Victron Energy has an isolation transformer available, however, it does not provide the ability to boost 208V power to 230/240V power, the weight is 56 lbs for each 7 KVA unit which is almost twice what the Mastervolt unit is running (although still half of what the Charles Industries Traditional Isolation Transformer) weighs. Thus, this unit is not a complete solution for the problem at hand, hopefully they will produce a unit which is capable of automatically adjusting the output voltage. The size is 362mm x 258mm x 218mm, weight is 26kg, cost is 990 Euro An alternative would be to use a step down transformer from the 230/240V line to create a 120V line which has a common neutral with the 230V system. By doing this all of the current single pole circuit breakers are acceptable. Essentially the inverter is doing the same thing because the neutral and ground of the 120V inverter are connected together to ships ground. Option 3) This option makes whatever power found on the shore power connection into something which looks like a home dryer circuit (which is one of the forms of common dock power) thus this becomes a US based system. Basically this option takes option 2 and adds an "Autotransformer" to the output of the isolation transformer to move the neutral point half way between the two phases. The only advantage I see to this type of system (other than looking like US dock power) is the ability to use either of the two phases as a 120V leg. Victron Energy has an autotransformer which is designed to do this which weighs about 28 lbs and is of the toroidal design. The size is 14.6 x 8.4 x 4.3" and is capable of handling 32A on each phase and on the neutral for 30 minutes and 28A continuously. It is not clear if it is an actively cooled device. Cost is about 470 Euro. This system does require double pole breakers on the 230/240V equipment because the neutral (and ground) are now half way between the L1 and L2 legs of the 230/240V equipment. Option 4) In this system only the battery chargers are connected directly to shore power. I am currently researching the question of if an isolation transformer is still needed to seperate the shore ground from the ship ground. As the battery chargers are "galvanically isolated" I think that the shore ground is connected to the AC ground of the battery charger and the DC negative is connected to batteries (and thus ships ground). If this is the case this solution becomes an interesting option. This setup is essentially two independent systems, a large battery charger and a set of inverters to produce the desired power aboard. Let's first look at the battery charger side of the system. The advantage of a system like this is that any input power form from 90 - 265 volts can be used, any frequency from 45 - 65 hz is acceptable, the boat load power factor is always 1, polarity reversal of dock power has no impact. Additionally, the generator can feed into the battery charger (two of the three chargers would fully load the generator), it could even be wired such that when limited dock power is available (i.e. only 1 or 2 battery chargers the generator can feed one or two additionally). Victron Energy makes a 100Amp @ 24V battery charger (Centar Charger Listing, Centar Charger Manual) which will consume approximately 15Amps @ 240V or 17Amps @ 208V. Thus, at 208V three of the units would consume approximately 51A which would fully utilize the available power on a 50A 208V circuit. The charger can produce full rated amperage at 29.7V over the entire acceptable voltage range assuming sufficient input current is available (Input voltage: 90 – 265 V Input frequency: 45 – 65 Hz Power factor: 1), size is 19 x 10 x 9.1" (505mm x 255mm x 230mm), and weight is 35 lbs/unit. Three of these units in parallel can provide 300A at 27.4V (Lead Acid Float Voltage) or about 8.2 KVA of DC power while in float mode, some additional power would be available (Perhaps 8.9 KVA) in absorption mode where the voltage is higher but this is a good starting point. It appears that the battery charger might be about 85% efficient if you assume that the charger is pulling 51A @ 208V to make 300A at 29.7V = 84% conversion efficiency. I suspect the number is higher but this is a good starting assumption. The idle consumption is an odd one as the battery charger is needed no matter what system is used. So this idle current will be ignored but the minimum power level for the inverter will be assumed to be the idle consumption. The 8 - 9 KVA of available power is not a limiting factor for peak output of the inverters as there is a large battery bank to handle peak demand, the average power with equipment cycling on and off must be below this value or the batteries will eventually run down. The list cost of each battery charger is 1432 Euro (~ $2140 USD) so the charging system hardware is about $6000 USD. The system can be setup and tested with a single charger if desired. I would prefer the microprocessor controlled Skylla-TG series which is 365mm x 250mm x 257mm, weighs 10kg, at a cost of 1484 Euro, however, the input voltage range is limited to between 180V and 400V AC at 45-65 hz. The Skylla 24/100-G claims in the brosure to run from 90V to 265V at 50 or 60hz, size is 365mm x 250mm x 257mm (14.4x9.9x10.1 inches) weight is 10kg (22lbs). These units are microprocessor controlled, can be used as a power supply, battery temp sensor provides compensated charging, no starter charging. Unfortuantely the Pheonix chargers are the only ones which have the 4 stage adaptive charging option. Mastervolt makes a similar battery charger producing 100A for a 24V bank for about $3100 per unit list price (Mastervolt Charegemaster 24/100-3) the weight is 9Kg, size is 420mmx318mmx144mm, the unit consumes 3600watts, 16A @ 230V, 32A @ 117V, voltage range 230V+-10% (207V - 253V) and 117+15% -10% (105V - 129V) which leaves a significant range between 130V and 206V where the charger will not work according to spec, it is unclear if it just won't produce full output or if it will cycle off. This would require three units for a total cost of $9300 for the charging system. Hopefully my estimate of price for the Victron unit is not optimistic or the Mastervolt unit retail price is somewhat lower than the list price. On the other side of the equation are the inverters to make power for the vessel, in this configuration all of the AC power on the boat has to be generated by the inverters and thus I need to be able to comfortably carry any normal combination of equipment at the same time. Thus, the first question is what is the "normal" peak demand which is under automatic control which the 230V inverters need to carry. 1) Main cabin/forward cabin air conditioner in cool mode 1600 watts, in heat mode 2000 watts 2) Aft cabin air conditioner in cool mode 1600 watts, in heat mode 2000 watts 3) Refrigeration Compressor 1500 watts This makes for 5500 watts of potential continuous load Additionally the following 230V equipment can be turned on and off selectively 4) Washer/Dryer 2000 watts (Tends to be very frequency dependent, have not found a 50/60 cycle version yet) 5) Microwave 1200 watts (could easily move to the 110V circuit) these also tend to be frequency and voltage sensitive. 6) Hot water heater 2000 watts The remainder will end up on the 110V circuit 7) general electronics (500 watts unless someone turns on a blow dryer! Which would be 1500 watts) Now, if using a DC based system it should be possible to move the hot water heater over onto the DC bus to avoid the inverter load which would help things considerably. So, the worst case load at any time would be 5500 watts + 3200 watts on the 230V circuit or just under 9KW A 1500 - 2000 watt 60 cycle inverter should handle the general electronics just fine (in fact, the trace inverter would be sufficient if I can determine why the voltage is 102V) Now, if the microwave moves over to the 110V circuit a 2500 watt inverter might be a good choice but 2kw would be sufficient. If the microwave moves to the 110V circuit then the total required would be about 7500 watts on the 230V circuit Now, as an example, the victron power inverter only boxes come in 3kw and 5kw, they are dip switch selectable for 50 or 60 cycles and since there is no power to match to there is no issue of when shore power comes on the frequency shifting to the other frequency. They are stackable and have about 2x surge capacity. So, a pair of 5KW units could carry everything without an issue. It would be possible to run the boat as both 50hz and 60hz if needed by having one inverter 50 cycle and one inverter 60 cycle however, they would have to NEVER be stacked in that configuration. 230V/240V Single phase 50/60hz capable inverters The Victron Pheonix 5kw inverter is sized 444mm x 328mm x 240mm ( inches), weight is 28kg, list cost 2625 Euro ($3924 USD) (525 Euro/kva, 5.6kg/kva) The Victron Pheonix 3kw inverter is sized 362mm x 258mm x 218mm ( inches), weight is 18kg, cost 1575 Euro (525 Euro/kva,6kg/kva) The Victron Pheonix 2kw inverter is sized 520mm x 255mm x 125mm ( inches), weight is 13kg, cost 1250 Euro (625 Euro/kva, 6.5kg/kva) 110V Single Phase 60hz inverters The Victron Pheonix 3kw inverter is sized 362mm x 258mm x 218mm ( inches), weight is 18kg, cost 952 Euro ($1250 USD) (317 Euro/kva) Unfortunately there is not a smaller unit until 750 watts which is too small to be useful Another option would be to use their "inverter with transfer switch" model and not hook up the input to anything. While this is a more expensive route (approximately $1000/inverter) higher than without the charger the ability to use the inverters in a more traditional mode (i.e. connected to shore power) in the event that this system does not perform as expected is a potential advantage. The Victron Quattro 5kw inverter/charger 444mm x 328mm x 240mm ( inches), weight is 30kg, cost 3470 Euro ($5209 USD) (694 Euro/kva, 6kg/kva) 4250 watts @ 25C, 3350 watts @ 40C, 10kw peak surge 25 watts idling, 20 watts AES Mode, 5 watts in search mode, 120 Amps Charging The Victron Quattro 3kw inverter/charger 362mm x 258mm x 218mm ( inches), weight is 18kg, cost 2535 Euro (845 Euro/kva, 6kg/kva) 2500 watts @ 25C, 2000 watts @ 40C, 6kw peak surge 15 watts idling, 10 watts AES mode, 4 watts in search mode, 70 Amps Charging The Victron MultiPlus 3kw inverter/charger 362mm x 258mm x 218mm ( inches), weight is 18kg, cost 2250 Euro (750 Euro/kva, 6kg/kva) 2500 watts @ 25C, 2000 watts @ 40C, 6kw peak surge 11 watts idling, 9 watts AES mode, 4 watts in search mode, 70 Amps Charging 110V Single Phase 60hz inverters The Victron Multiplus C 2kw inverter/charger 520mm x 255mm x 125mm ( inches), weight is 13kg, cost 1501 Euro (751 Euro/kva) The Victron Multiplus 3kw inverter/charger 362mm x 258mm x 218mm ( inches), weight is 18kg, cost 2082 Euro (694 Euro/kva) The Victron Multiplus 5kw 120/240 inverter/charger 444mm x 328mm x 240mm ( inches), weight 30kg, cost 3470 Euro (694 Euro/kva) The Victron inverters are capable of being programmed for split phase, three phase, and two phases of three phase power modes. It might be possible to configure a system which would support the common forms of US power but the voltage would have to be adjusted. I need to talk with Victron about if this is a change of taps or a completely different inverter. The Multiplus inverters have two outputs, one is always hot, the other is only active when shore power is available. Programmable for 3 phase operation, software programmable. Mastervolt has several 5kva inverters which are in the $8,000 range, So, assuming we need 7.5 - 9kw of continuous output (depends on the microwave) that means we need either two of the 5kva (8500 watts @ 25C, 6700 watts @ 40C, 20kw peak) inverters or three of the 3kva (7500 watts @ 25C, 6000 watts @ 40C, 18kw peak). Even if the microwave remains on the 230V circuit as long as it is not run at the same time as everything else we are good. The nominal "heavy load" is probably both air conditioners and the fridge which would draw 5500 watts which can be handled at the 40C derated power level of either configuration). Which configuration to pick is mostly determined by which will fit in the available space. The weight is very similar either way. One advantage of the smaller (3kva) unit is that if the auto-shutdown of the cluster works as expected the idling current of the pair of 5kva units would be 25 watts, the three 3kva units would be 15 watts. If all units are up though the pair of 5kva units would be 50 watts, vs 45 watts for the 3kva units. Another interesting trade-off of the 3kva units would be if two were running one frequency and one was running the other frequency. That would give 6kva on one circuit and 3kva on the other circuit, vs 5kva on both... The air conditioners must live on the same inverter as they share a cooling water pump which would be 4kw in heat pump mode so a single 3kw unit can't handle that. The 5kva unit can at 25C but not at 40C, in AC mode the pair of air conditioners draw about 3kw which the 5kw unit should be able to handle at 40C. It is unlikely that the units would overheat when both AC units are running in heat mode so that works. There is no reason at this point to run any of the 230V equipment at 60hz. If using 3 of the 3kva units, the fridge, microwave & washer/dryer (1500 watts, 1200 watts, 2000 watts) would share a 2500 watt inverter. If the microwave was moved to the 110V circuit then there would be 3500 watts in use, one could load shead the fridge during the short peak requirement for the washer/dryer if necessary. However, the pair of 5kva units is probably a better match. Both are the same cost. Luckily with the exception of microwaves and washer/dryers (1200 watts & 2000 watts) the rest of the equipment will happily run on 230/240V @ 50/60hz. Since microwaves are cheap you could change it out as needed or run off the 110V inverter which is always 60hz. Thus, the washer/dryer defines the preferred frequency for the boat. So, assuming two 5kva inverters in parallel (2 @ 2625 Euro = 5250 Euro) and three 100Amp battery chargers (3 @ 1432 Euro = 4296 Euro) = 9546 Euro or ~ $13.4K USD If I use two Quattro 5kva inverters in parallel (which provides a fallback in a 230V/240V environment for a more traditional inverter/charger setup) (2 @ 3470 Euro = 6940 Euro) and three 100Amp battery chargers (3 @ 1432 Euro = 4296 Euro) = 11236 Euro or ~ $15.7K USD @ 1.4USD/Euro Thus, the cost of the additional charging and transfer switching capability is about $ 2300 USD. If the feature was not to get in the way it might be worth it to keep the capability? There appears to be no weight or size hit for doing so. If the inverters are capable of being programmed for 50 or 60 cycles and can be used with 230V european power as well as 240V us power it might be an interesting option. Probably ends up looking like the solution with an isolation transformer pack. If the 1500 watt trace inverter from 1997 is not to be used then the Victron 3kva unit would be a good choice for making 110V power at a cost of 952 Euro ($1.4K USD) Thus, with Victron Energy the total of three battery chargers and three inverters (2 - 5kw at 230V & 1 3lw at 110V) would give a total system cost of $14.8K - $17.1K USD Total weight is 3 35 lbs + 2 * 66 lbs + 1 * 40 lbs = ~280 lbs There would be a total of 6 boxes to install, however, the old battery charger and the old trace inverter would be removed for a total of 4 new boxes. All of the circuits would remain single phase thus a new power panel would not be necessary although it might be adviseable for other reasons. The cost and weight of this configuration is similar to the A/Sea system (somewhat less actually as the 110V inverter is already included), however, this configuration provides full capability on shore power, generator power, and battery power. With a larger alternator (100 - 200 amps) full capability would be available for long distance motoring as well. Idling power use should be about 25-50 watts compared to the A/Sea solution consuming 300 watts idling, this does not include the idling current of the battery chargers. Asssuming that the three battery chargers connected to the same bank will have the same idling current of a single battery charger it is basically a wash as the betteries do have to be charged in any configuration. Overall power efficiency should be about 85% going from dock power to boat power (90% efficiency for battery charger, 95% efficiency for inverter) or about a 15% increase in my power bill for a given load. If the base load is 50 watts that would be 1.4KWH/day at 19c/kwh or $0.23/day, $7/month, $83/year in increased power bills compared to a direct connection. Using inverters which can be adjusted to 50 or 60 cycles 230 or 240 volts makes the solution convertable to look like local power anywhere on the planet in the event the boat is permanantly moored in Europe or the US. Ideally the three chargers would be wired to allow pulling power from the 125V (30A or 50A), 240V (50A), 230V (50A), and the generator. Each charger would have a 4 pole break before make three position switch for shore 1 (two phase power), shore 2 (single phase power), & generator, ideally a 4th position would be provided for "completely off". This would allow multiple forms of power to be used when available, unique adapters would be made up to deal with various unique power forms. If all grounds are kept clean it should be possible to charge from a limited shore power source and occasionally run the generator to provide additional power when needed. Remaining questions: Do the battery chargers provide complete, safe isolation of the shore ground from ships ground (avoiding the need for the isolation transformer) Option 5: Use a power converter like those provided by A/Sea Systems in Huntington beach. These systems can use power from 160V to 260V between 40hz and 70 hz to make either 230V power, 240V split phase at either 50 or 60 hz. The downside is that you still need an inverter as this is an AC to AC converter, it weighs 230lbs, and it consumes 300 watts idling or about 300*24=7200 watt hours/day = 7.2 KWH/day. Now, power in LA is about 19c/kwh so this costs $1.38/day, $40/month or about $500/year in increased electric bills! The cost for such a unit is in the neighborhood of $15K - $20K USD depending on capacity and features. Since an inverter is still needed away from the dock a unit capable of handling at minimum the refrigeration system would be required. The generator would be connected to the A/Sea system also to have a single type of power on the boat. Note that either a step down transformer or a second inverter would be necessary to create 110V power. Additionally, either the inverter needs an internal battery charger or an additional battery charger would be necessary. Note that the efficiency is reduced because AC power is converted to DC and then back to AC in this box and then the battery charger converts the newly created AC back into DC to charge the batteries. It is not clear if the A/Sea system is compatible with inverters that support the shore power connection due to the potential for shore duration backfeed conditions which might exist. Option 6: Convert the boat to use 240V split phase power directly, some form of galvanic isolation is still necessary, double pole breakers are required, an inverter is required to avoid having to run the generator to chill the fridge, make popcorn, etc. The boat cannot use anything but 240V split phase power... This option would only make sense if a transformer was on the dock to make 240V split phase power. Basically you are very dependent on the shore power connection being exactly what is expected. At least most of these systems are self sensing such that if shore power is not as expected it will not be allowed on the boat. If I had not found out that the 208V 120 degree phase power is just as likely as 240V split phase power systems I would have built one of these and then had trouble. Option 7: Convert the boat to use 208V 120 degree phase power directly, some form of galvanic isolation is still necessary, double pole breakers are required, an inverter is required to avoid having to run the generator to chill the fridge, make popcorn, etc. The boat cannot use anything but 208V 120 degree phase power... Inverters to support this power form are difficult to find (Victron Energy inverters are capable of have several independent inverters bound together to make three phase power or two legs of a three phase system). Not a viable solution. Option 8: Convert the boat to use each leg of the power form directly. i.e. run everything off of 120V power and treat it as two 50A circuits... This requires replacing all of the AC units, the Fridge compressor, microwave (need to replace anyway), the washer/dryter (need to replace soon), and the hot water heater element. Generator would have to be rewired to run 240V @ 35 Amp split phase power (and monitor phase imbalances carefully) or rewire to 120V @ 70A. Most of the wiring on the boat would have to be upgraded for the higher current of 120V circuits. This is the other extreme solution, several inverter solutions do a nice job with this situation where some of the high load outputs are not powered when single phase power is available. However, once you go down this route the vessel is now US unique. All AC equipment on the boat would be replaced. Now, an interesting question is if you go down the road of the 230V/240V single phase system can you get here if it turns out to be the right solution. The inverters would need an "autotransformer" to create two legs (i.e. 240V split phase power), the cost would be fairly minimal and if high frequency transformers are available the weight should not be horrible. However, the cost of converting the ships wiring is pretty high in terms of labor but you end up with all new equipment. Other notes as I work through the conversion process: Debugging existing Trace 110V Inverter