Frequently Asked Questions --Topics:
Why did you replace the Lister Blackstone main engine?
What can you do about noise and vibration?
How much fuel do the Fleet Tenders use?
What about fuel capacity? Can they cross the Atlantic?
And water capacity?
Whatís involved in converting a DC boat to AC?
What about a bow thruster and a get-home?
Do you have heat and air conditioning?
How are they maneuvering in close quarters? How are they at sea?
How many people do you need to run one?
Which of the classes do you like best?
What else do I need to consider?
Some comments on MCA rules
Whatís involved in going from European Power (230VAC 50Hz) to USA (240VAC 60Hz) and back?
Why did you replace the Lister Blackstone main engine?

Lister BlackstoneI really love the Lister -- plodding along at 750 revs, it's more or less bulletproof, dependable, belt and braces (belt and suspenders over here) with three cooling systems, two lubrication systems, easy to work on, a great engine, and it hurt me to take it out.

However, it has its negatives -- you have to go down to the engine room to start it and it has oil cups slopping oil around. Both of these problems can be fixed, but the remainder are harder. Like the GMC two-cycle diesels there were so many of them produced that parts will always be available, they're not getting any cheaper -- one of Fintry's sister ships paid 3,000 Euros for a starter recently. In the USA, where we expect to sell the boat in fifteen years (God willing), no one has ever heard of a Lister. It's big -- height and width are not a problem, but it's very long and has a bunch of auxiliaries that take space. Most important, it's a hard mounted four cylinder engine and the vibration is always with you -- when we took Ilchester around Scotland, there was always something vibrating.

Cat 3406 The Cat 3406 is great. The first time we took Fintry out after the Cat was installed, I accelerated out of the inner harbor at Portland, to about 1500 RPM and the boat was smooth as silk -- I thought we were doing around six knots. I looked at the GPS and we were doing nine. The soft mounts are so good that you feel no vibration at all when you put your hand on the bottom of the engine mount.

The 3406 is available at horsepower ratings starting at 360 and going up to over double that -- I saw a pair rated at 700 horse in a UK government fishing patrol boat at the SeaWork show in Portsmouth. While certainly the Lister is the gold standard for dependability, the Cat purrs along at around 1350 RPM to produce eight knots, putting out about 150 horsepower. I can't believe that for practical purposes it won't be just as reliable as the Lister.

The Cat just in place The Cat is close to being a drop in -- the engine mounts sit easily on the existing rails and the height is appropriate for the shaft, assuming you use two constant velocity joints in an intermediate shaft to allow soft mounting the Cat. The only serious fabrication required is the mount for the thrust bearing at the end of the original shaft (without CV joints, the original setup took the propeller thrust on the gearbox. The CV joints canít take the thrust, so you have to install a thrust bearing between them and the shaft.) Itís available with several gearboxes that provide the correct output shaft speed of around 375 RPM.

The Cat going in Getting the Lister out in one piece is difficult -- we had sold it, so this was essential. While there are soft patches both outboard and above the engine room, they arenít big enough. The whole wheelhouse, funnel, and main deck above the engine room unbolts, but this seemed like overkill. In the end we cut out the piece between the top soft patch and the side one, which provided a hole that was big enough. TheCat went in the same way, but much more easily.

What can you do about noise and vibration?

Propeller Aperture Some of the vibration undoubtedly comes from the Lister-Blackstone. As noted above, replacing it with a soft mounted engine will reduce vibration significantly. The other major step, much easier, is to modify the propeller aperture to allow the pro wash to flow more smoothly. This year we removed the two eyes outboard of the propeller that are circled in the photo. At her next haulout, we will also remove or fair the stub of the keel (the smaller circle) which also protrudes into the propwash. The removal of the two eyes made a big difference under some sea conditions on our travels after removing them.

Neither the Cat nor the Lister-Blackstone is particularly noisy. A well set up dry exhaust system will generally be quieter than a wet exhaust, and there is plenty of space in the funnel for a good muffler.

How much fuel do the Fleet Tenders use?

Crossing the Atlantic, we ran at eight knots, burning almost exactly eight US gallons per hour (one US gallon is 3.8 liters -- eight gallons is about thirty liters), including moderate hotel loads on one 9kW genset. We changed the oil on schedule at Horta, but otherwise, she just purred along.

A chart prepared by Milbrookís engineer during several of her trips suggests that the Lister Blackstoneís consumption is about the same. That same chart says that at ten knots, consumption goes up to sixty liters per hour, a 60% increase in consumption per mile. Headwinds will have a similar effect. Speeds slower than eight knots donít reduce consumption much.

What about fuel capacity? Can they cross the Atlantic?

A standard fleet tender has about a 1,200 mile range with a 10% safety margin. The easiest route across -- going to the Azores and then straight from there -- is about 3,200 miles, with a longest leg of around 1,900. There are several other ways to go, within the 1,200 mile limit, however:

  • Two of them are operating far up the Amazon, in Peru, having crossed via the southern, trade winds route, with drums of fuel on deck.
  • Milbrook had a quick and dirty tank of about 1,000 US gallons (about 4,000 liters) welded to the forward side of the bulkhead between the #1 and #2 holds and has crossed the Atlantic both ways.
  • It's also possible to cross via the Shetlands, Iceland, and Greenland well within the 1,200 mile range.
  • Finally, at considerably higher price you can put one aboard a yacht transport vessel which will bring her across dry. This would require driving her to a pickup point, probably in the Med.

    Since we expect to cruise long distances regularly, while Fintry was in England we raised the floor of #2 hold one foot from frame 19 to frame 28 (all but the two end frames) for two fuel tanks -- each around 7,200 liters. This, with the engine room tanks, gives the 5,000 mile range required to do a circumnav (we're not planning on going around again, but felt that the boat should have that capability).

    Racor FBO-10 While we're on the subject of fuel, note that the original fuel filters are all relatively coarse wire gauze, which are nowhere near what is required for modern engines. Racor makes a high capacity filter (FBO-10) which will handle the output of the fuel transfer pump, so that all of the fuel in the day tank can be filtered in advance.

    Racor 900 Filters We then have a pair of Racor 900FH filters in parallel between the day tank and the four diesels and, of course, filters on each engine. If either of the 900FH filters needs replacement, two valves switch the flow to the other one. Since the day tank is above all the engines, priming and air bleeding is very easy.

    While smaller sizes will handle the flow requirements, experience has taught me that the large filter elements in a 900 series filter are only a little more expensive than the elements for smaller filters and will last a lot longer if the fuel isn't completely clean. This isn't an issue in the developed world. but is very much one in the third world -- on our circumnav, we once clogged a filter in only ten hours.


    And water capacity?

    We raised the floor of #1 hold twenty inches to gain two new freshwater tanks -- each around 2,000 liters. We did this because it is now known that bitumen is a carcinogen and Manor Marine told us that removing the original bitumen coating in the existing water tank would be almost impossible. We use the old freshwater tank for toilet flushing on long trips. An alternative would be to accept the fact that you shouldn't drink the tap water and carry lots of bottles.

    Whatís involved in converting a DC boat to AC?

    The early Fleet Tenders (from Aberdovey through boats a little later than Fintry) were equipped so that most systems ran on 220VDC. All of the boats also have 24VDC systems for engine starting and emergency lighting. The later boats have 230VAC systems. Since DC isn't very useful on a yacht, many of the DC boats have been converted to AC.

    Northern Lights 9kW Gensets Having converted a DC boat, I think I'd almost rather have a DC boat to start rather than an AC boat -- certainly it's close to a toss-up. Going DC to AC, you have to change out the gensets, or at least the electric ends. That's fairly easy either way as most of the diesels on the boats have been used as both AC and DC sets and the ends are readily available. We put in two Northern Lights 9kW gensets in place of the smaller existing DC set and put an hydraulic pump in place of the the other DC generator (see above). You also have to change the shore power connection and add one or two isolation transformers.

    All the lights will run either way (fluorescent ballasts that run on DC will generally run on anything and incandescent lights are omnivorous). We replaced the motors on the fuel transfer pump and the steering pump (using three phase motors driven through variable frequency motor controllers which run on single phase), changed the windlass to hydraulic, and put DC motor controllers running on 240VAC (US$80 each) on the engine room blowers. DC relays won't run on AC, so we had to put a full-wave rectifier (US$10) on the supply for the relay in the navigation light controls and the water heater (calorifier) control. You could, for a little more money, change the relays themselves.

    With all this done, we have a simple AC system, similar to most USA residences, with 240VAC from a generator, an inverter, or shore power, and a center tap providing 120VAC where needed. Everything is single phase, except for three-phase motors whose controllers take single phase input.

    AC Electrical Schematic The boats that were built as AC boats have complex, three-phase systems, that run 440/230/120VAC 60Hz. You need 440VAC three phase shore power, available only in the very largest marinas, to run any of the motors and you need to pay attention to keeping the three phases balanced on your gensets (this is hard if you're running an electric clothes dryer or water heater). Inverters that supply three phase power are not readily available, so you have to run a genset when not hooked to shore power. And, the AC boats have 11 distribution boxes around the boat.

    There's one other significant difference between the AC boats and the DC boats. In the DC boats, the engine room runs from frame 6 to frame 18 . The space from frame 2 to frame 6 is two large tanks P&S and a void in the center. The tanks can be used to adjust the trim of the boat, either F&A or P&S. We normally run with them full; emptying them will raise the stern about 15". While this will make the boat less stable, it might get you off a shoal.

    (It's conventional to refer to locations on boats this size and up by their frame number. Frames are spaced 20" apart, frame 0 is at the rudder post and the forward waterline is at frame 45. All the bulkheads below the main deck are located on a frame.)

    The AC boats, on the other hand, have a transformer room the full width of the boat from frame 2 to frame 7, and voids below, with solid ballast. The engine room is, therefore, one frame smaller, but the transformer room has a lot of empty space which could be used for various purposes.

    So, the choice between an AC boat and A DC boat is not straightforward. Shorepower is a problem for either -- there was 220VDC at Manor Marine, an ex-Navy base, but I've never seen it elsewhere in the civilian world. 440VAC 3 phase 60Hz power is also rare, except at the very largest marinas in the USA. Since only emergency lighting runs on 24VDC, you need shorepower or a running genset (or inverter) to do almost anything.

    Since we knew we were going to do a major rewiring, a DC boat was fine with me. I like the versatility of having the tanks aft.

    If you've never dealt with three phase power, read the Wikipedia article Three-Phase Electric Power

    By the way, all of our AC electric distribution, which originally occupied an engine room box 60"x30" by 72" high plus various auxiliary boxes around the vessel, and had hundreds of fuses, is now in a single box that is 8"x24"x84" high plus one auxiliary box 16"x20"x8" deep. Itís all DIN rail mounted circuit breakers -- no more fuses.

    What about a bow thruster and a get-home?

    As part of the conversion from 220VDC to 240VAC, we took the DC generator end off of the Perkins 6-354 -- the larger genset -- and put on a 60hp hydraulic pump. It drives a 60hp bow thruster, the windlass (which was 5hp 220VDC electric), and a 60hp motor mounted above the propeller shaft, with overgrown bicycle chain sprockets on the motor and the shaft for use if the main engine fails. Estimate is it will do 4 knots.

    The bow thruster is a real pleasure. With it, itís easy to move the boat sideways -- parallel parking in a short length. With the rudder hard over, the propeller acts like stern thruster, although, of course, you have to turn the propeller forward to go sideways and then reverse to keep from moving forward. Also, at idle the boat moves about three knots, so if you want to go very slow, you have to be in neutral. The bow thruster provides steering then, when thereís little water going past the rudder.

    I've been asked if we could get away with a smaller bow thruster. Given my comments elsewhere in this FAQ about how easy they are to handle without the thruster, I could agree that a smaller thruster would work. The limit is basically how strong a wind the thruster will push against and how much sail area there is. If you don't extend the deckhouse forward, you could get away with less. Our naval architect calculated a 50hp thruster for a wind of 25 knots; we rounded that up to 60hp. As the crosswind gets up into the twenties, the bow will go upwind, but it clearly takes longer, so I'm happy with the decision. In thinking about this, remember that the wind thrust varies with the square of the wind speed, so a 25 knot wind is 56% more thrust than a 20 knot wind.

    Do you have heat and air conditioning?

    The early Fleet Tenders, at least all the DC boats, have 1,000 watt radiant heaters scattered around. None of them have any cooling. Some of the later boats have large three phase electric air heaters mounted near the funnel and distribute heated air throughout, with ducts carefully set up so you can control fire and flooding.

    Way Wolff Boiler I've never thought much of electric heat, particularly underway, when the main engine will be throwing off ten times the energy that you need to heat the boat in any climate. So we've replaced the electric heat entirely, except for summer domestic hot water while on shore power when we use an electric water heater (calorifier). HVAC is piped heated/chilled water. Heat is a 50,000 btu Way Wolff diesel boiler (Way Wolff supplies most of the smaller vessels of the US Coast Guard). There's a heat exchanger on the CAT for use underway and on the gensets for mooring/anchor use. The system also supplies domestic hot water. The chiller uses the same piping.

    Speaking of domestic hot water, note that the existing water heater (calorifier) is designed to work with the water pressurized only by the header tank one deck up -- much less than the usual pressure in a domestic water system. We had removed the header tank and installed a 24VDC water pump before we crossed the Atlantic. Although I had recognized the problem and had installed a pressure reducer on the supply to the hot water heater, the tank was troublesome throughout the trip, constantly spring tiny leaks.

    How are they maneuvering in close quarters? How comfortable are they at sea?

    Fintry is very easy to handle, even without her bow thruster. Without the thruster, I just put the bow into the float, put a spring line ashore, put the rudder hard over the other way and idle forward. The stern pulls right in. Since the rudder has virtually no effect below three or four knots unless the shaft is going forward, you have a built-in stern thruster available all the time. She's so heavy that the wind has little effect. One of her sisterís owners has been known to dock his boat (no thruster) single-handed, running down the stairs to put the line ashore. We don't do that, but Dee and I actually prefer it if there are no helpful strangers on the pier, as it's easier for the two of us to do it than to convince strangers to do it our way. We can also turn her in her own length without the thruster if there's not too much wind, something we have to do to get her out of her slip.

    The new power steering, installed in 2014, is a compact pump and valve combination package that runs on 230VAC. It allows us to steer with a joystick, and runs off the autopilot, which we use most of the time. The original manual helm pump, thirty turns lock to lock, is still there as a backup. It is much quieter than the Donkin power steering pump in the engine room.

    Speaking of autopilots, there is none in the original design. I have seen three different kinds of installations.

  • The first is to put solenoid valves in the hydraulic power steering. These can then be controlled directly by most autopilots. This is the setup Fintry has. It's quiet and precise.
  • The second is to put an autopilot pump in parallel with the helm station, in the wheelhouse, together with valves to switch from the helm pump to the autopilot. This has the advantage that you don't have to drain the entire hydraulic system to make the installation, but it's noisy and has to be switched manually.
  • The third is to use a belt drive, the same systems that are used for cheap installations in small sailboats with wheels. These are also noisy and not very precise, but they're cheap.

    Fintryís very comfortable at sea until it gets fierce -- at 35 knots on the nose during our Atlantic crossing, it was bouncy, both pitch and roll, but most boats her size would have been similar or worse.

    How many people do you need to run one?

    The RMAS ran them with a crew of five to seven. When underway, Fintry had a minimum of a watch keeping officer, an engineer whose station at sea was at the engine telegraph in the wheelhouse, a separate helmsman, and a lookout or two.

    We operate Fintry in all but the busiest harbors with one person in the wheelhouse.

    The only times you need more than one person are:

  • coming to a mooring or alongside a wharf
  • in waters that are tight enough (nearby shoals or traffic) that you can't leave the wheelhouse for five minutes.
  • in traffic sufficiently heavy to require a second set of eyes near the wheel.
  • Dee and I operate Fintry regularly in Boston Harbor, which is certainly as busy as Portsmouth or Plymouth, maybe worse. Either of us alone can bring her alongside her wharf (actually a floating barge) unless the wind is fierce off the barge. The bow thruster helps, but is by no means essential -- point the bow at the place you want to be, go ahead until you touch, then rudder hard over away from the wharf and let the prop push the stern in, killing forward way with reverse as needed. For those who are used to running fiberglass boats, remember that docking a large steel vessel with an 8" rubrail (20 cm fender) is a contact sport. This is not to say that you can be careless while docking. 150 tons of boat can make a big dent if you hit something too hard, but it does mean that you have more ways to control the situation.

    Which of the classes do you like best?

    I can't speak to all of them. I've been to sea on Loyal Watcher, Ilchester, and Fintry, and been aboard half a dozen others, including Milbrook, so I've at least been aboard all of the classes except the Aberdoveys. For brief descriptions of each class see The 79' Fleet Tenders of the Royal Navy

    We lengthened the wheelhouse (fore and aft) by four feet, which makes a huge difference. The standard wheelhouse is good for maybe three people, Fintry's is good for eight. The wheelhouse (and everything else above the upper deck) is aluminum so this was actually quite easy. And, of course, before we bought her, Serco and the RMAS had extended the saloon forward by about 21 feet (about 6.6 meters). Many of her sisters have been similarly extended.

    A typical Clovelly Class Fleet Tender The Clovellys, Dive Tenders, and Loyals are essentially the same, except for the deck layout, which is easily modified. I'd rather take the empty holds of one of the Clovellys and lay it out to my needs than one of the Loyals and have to work around (or scrap) all the existing stairs and cabins.

    A typical Dive Tender The Dive Tenders have a longer deckhouse forward and a full width upper deck aft. I like the full width deck aft -- we added it to Fintry -- but the full width deckhouse makes docking harder, as you must go through or up and over to get from bow to stern.

    A Manly Class Fleet Tender The four Manlys, I think, are also less desirable, for the same reason -- their deckhouses extend all the way out to the sides as on the Dive Tenders. That would be a nuisance after you're alongside and started putting on normal dock lines. Their only particular virtue is a longer wheelhouse.

    The boats with AC electric equipment (after 1972, approximately) have a passage from the engine room aft to the steering flat and the space that is three aft tanks on the DC boats are a transformer room on the AC boats, with a lot of room left over for storage and other equipment. On the other hand, without the tanks, you have less flexibility in trim and draft, particularly if you build in large fuel capacity.

    An Aberdovey Class Fleet Tender The Aberdoveys, which I've never been aboard, certainly have much less space in the same hull. The wheelhouse is probably a bit more comfortable in a real blow -- itís lower and, therefore, closer to the roll center.


    What else do I need to consider?

    This section is by no means complete. I'll add to it from time to time.

    Since what follows is mostly negatives, let's start with a few positives:

  • They were well and solidly built. The bow is particularly pleasing.
  • Probably because there are so many of them, they can be bought for less money than other similar sized ex-government boats. In our search for Fintry, most of the other boats were much more expensive.
  • The hull form is very good. Our Naval Architect's comment before we bought Fintry was:
  • The wheelhouse is amidships. We looked at several forward wheelhouse boats in our search, but concluded that they would be very uncomfortable in a head sea.
  • They have a modest draft -- less than eight feet at sea, and less than seven feet if you pump out all the ballast water -- not wise at sea, but probably OK in sheltered waters.
  • They are easy to handle.
  • With the main deckhouse and the wheelhouse extended, there's a lot of room inside.
  • The engine room is large and easy to work in -- even better with both the Lister-Blackstone and the electrical panel gone.
  • The original water systems are very basic.

    Fresh and Salt water header tanks.Salt water for toilet flushing and fresh water for all other domestic purposes are supplied from two header tanks on the upper deck. Saltwater is pumped up by using either of the two pumps connected to the bilge, ballast, and fire system. The freshwater has its own automatic pump (on Fintry, this pump is identical to the fuel transfer pump, so when we replaced the water pump, we gained a spare for the fuel transfer). While the header tanks are lagged, presumably to protect them from getting too hot, they are not protected from freezing. And, of course, the sewage flows directly overboard, above the waterline.

  • They are designed for relatively large crews, and most things are not automatic. There is no autopilot and while the original electronics often work, they can't be called modern.
  • Their condition varies widely. A recent coat of paint may hide many sins that will need repair. The cheaper boats for sale at any one time will often prove the most expensive over the first 3-5 years, even if you are able and willing to do much of the repair work yourself.

    Some comments on MCA rules

    First, I should say that as an American owner of a Fleet Tender, I am not governed by the MCA rules and therefore know just enough to be dangerous. This is here because several people have asked about various aspects of getting an MCA certificate.

    Fintry had a MCA Class VI and an MCA Class IV certificate simultaneously. They were both very limited -- the former to "Within the limits of the Dockyard Port of Plymouth" and the latter to "Within Plymouth Sound not Seaward of a line drawn from Cawsand to Breakwater to Staddon." I have originals of both certificates as well as her stability book if that would be helpful to anyone. I also have copies of stability books for Milbrook and Fulbeck. I also have basic stability and trim calculations in an Excel spreadsheet.

    As built, the Fleet Tenders were Lloyd's 100A1  for navigation from the Elbe to Brest, which is, of course, a far cry from Plymouth Harbor. My Naval Architect (who specializes in vessels of this size for offshore use) is satisfied that the Fleet Tenders are safe for use anywhere in the world, although not the North Atlantic in winter or for an extended voyage in the Southern Ocean.

    The RNXS Fleet Tender Handbook (1990) believes that the Fleet Tenders have, without an engine room bulkhead, single compartment stability -- that they will float upright with any single compartment flooded -- so I do not understand why Fintry was subdivided.

    One possible explanation is that the engine room in Fintry and, I think, all the DC boats, extends from frame 6 to frame 18, 12 frames, or 240 inches. In at least some of the AC boats, the transformer room occupies the space that is ballast tank on the DC boats (frame 2 to frame 6). The transformer room is one frame larger (frame 2 to frame 7), so that the engine room in at least some of the AC boats extends from frame 7 to frame 18, one frame less. Note that the #2 hold is also 11 frames long (18 to 29), so in a boat with an 11 frame engine room, the largest space would be the #2 hold, not the engine room. It is possible that the RNXS handbook is generalizing from the AC boats....

    By the way, as built they are 79 feet exactly when the keel is level. I believe that it would be fairly easy to remove 3.5" to get them under 24 meters (at which length much tougher rules apply). The stern has a small curve in plan view, so that if you burned off the stern plate, then cut the framing forward 3.5", flattening the curve, and welded on a new stern plate, you would have a 23.95 meter boat. The stern framing is very heavy and, although I'm not a naval architect and am not really qualified to suggest it, it looks like you could simply remove the metal and not add any. There's adequate space in the steering flat to do the work, although a small person would find it easier to do the welding.

    There are two places you can save significant space in the engine room. One, by replacing the electrical panel which is 6 feet by 2.5 feet by 5 feet high, mostly air. Fintry's new AC panel, all DIN rail circuit breakers, is 24" x 6" x 6 feet high. Since the existing panel has access space behind it, you free up floor area close to 6 feet by eight feet. The other space saver is to convert the Lister Blackstone to wet sump and eliminate the sump tank which is against BH 18 on the starboard side.

    Whatís involved in going from European Power (230VAC 50Hz) to USA (240VAC 60Hz) and back?

    1) Voltage -- Europe is either 220VAC or 230VAC nominal (varies from country to country) while USA is 240VAC nominal. In practice, there's no real difference so you don't have to worry about it So, in everything below, I'll call it 230V and 115V. You must change the voltage appropriately -- the wrong voltage, either way, will fry most equipment. The only exceptions are that a lot of modern electronics has universal inputs which can take either 115 or 230V.

    Generally the shore power voltage can be changed at an isolation transformer where the power comes aboard. If you are converting a DC boat (see above), use a multi-tap transformer so you can adjust for often low marina voltage.

    2) Frequency. The USA runs on 60Hz; Europe runs on 50Hz. There are all sorts of good technical reasons why you should not run equipment designed for one frequency on the other one. Running 60Hz equipment on 50 Hz risks transformers getting hotter and cooling fans running slower, so overheating and fire is a risk. Running 50Hz equipment on 60Hz risks overloading motors -- things like fans and compressors use much more power at higher speeds.

    However, my experience is that almost everything works fine on the "wrong" frequency (in either direction). Specific experience:

  • If the label says that 50/60 is OK, then itís OK. This is true of many modern electronics boxes -- computers, music systems, and the like. Several USA designers of consumer electronics have told me that their equipment is fine on 50Hz or 60Hz, but their labels say 60Hz because it requires more testing for UL or CE to get both frequencies on the label. If you want to be particularly safe, note that much more non-USA equipment has dual frequency labels than USA equipment, so you can buy European appliances labeled for 230VAC 50/60Hz and be sure youíre safe. That has the additional advantage that using 230V rather than 115V is more efficient as well.
  • We had a cheap British 50Hz under counter refrigerator on Fintry. A compressor running 20% faster should be a serious no-no, but it ran happily 24/7 eight months a year from 2005 until we replaced it in 2012 as part of the new galley installation.
  • A tube style TV will require adjustment because the vertical rate is synced to the power line frequency, but we ran a 50Hz TV bought in Thailand on Sweetwater's 60Hz until we got home nine months later. Note that TV has other issues -- incompatible systems (NTSC, PAL, and SECAM), which a multi system VCR will solve.
  • Air conditioning compressors are an issue. Marineair says that their compressors run happily on either frequency, but put out less chill at 50Hz. Aqua-Air says that this is a serious no-no, that you cannot run the type of compressor that both companies use on two frequencies. We solved this on Fintry by using a three phase compressor and a motor controller that will take either frequency input and provide 60Hz 230V 3 phase output. Motor controllers also have the advantage that they can be programmed to soft-start large motors, so the lights won't dim when the AC compressor starts.
  • Some motors will run at the wrong speed. Most small motors -- handheld power tools, small kitchen appliances -- are "universal" and don't care about frequency. Larger motors (those that run at 3450, 1725, or 1150 rpm on 60Hz) will run at 5/6 of that speed on 50Hz and vice versa. This will include dishwashers, washer/dryer, and other similar things. That shouldn't be a problem, although cooling might be an issue (many such motors have built in fans to cool themselves. Running slower, the fan puts out less air, but the device will use less power at the slower speed). Mechanical clocks will run at the wrong speed. Digital clocks, it's hard to say -- most use the power line for a frequency source, so will run wrong, but some use crystals or sync to TV or cell phone time signals.
  • Fintry's cheap USA microwave ran perfectly on 115VAC 50Hz in England except that its clock ran slow (our isolation transformer converted the incoming 230V).
  • Fintry came with fluorescent lights everwhere on the main deck. Because she was a 220VDC boat, the ballasts were marked for DC/50/60. Although I haven't looked for them, I suspect that such ballasts are available for general use, but you might have to buy them in Europe.
  • Most modern battery chargers use switching power supplies and don't care about frequency. A few older ones will not work or will fail. Read the label.

    There are, by the way, two major technical reasons why 60Hz is better for all purposes.

    The first is that 60Hz goes through a transformer more easily, so transformers can weigh and cost less.

    The other is that a 60Hz generator will usually run at 1,800 RPM. (Itís possible to run them at 3,600 or 1,200, but the former wears out quickly and Iíve never seen the latter in sizes we use.) A 50Hz generator will run at 1,500RPM. The problem with 50Hz is that it will be the same diesel engine driving the genset at either 1,500 or 1,800 RPM, so the units cost the same, but the slower speed puts out less power, so a 50Hz genset costs more per kilowatt. The fuel consumption curve also favors the higher speed, so the 50Hz gensets also burn more diesel fuel per kilowatt produced.

    Iíll guess that this is why the AC Fleet Tenders (and, I am told, all NATO Naval Vessels) are 60Hz.