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| Power Man. System | Power Generation | Wiring Analysis | Cable Inst. | Elec.Winch | In Hindsight |
Chapter 25
Electrical / Refrigeration
(Full Text, no Data & partial Photo's)
As I understand it, in Australia a pleasure craft is considered to be an appliance as it is not connected to the grid and not subject to the Supply Authority regulations. If building to Survey then the relevant State authority covers it.
The absence of a set of rules makes it hard to determine what is a practical, safe and sound and for guidance I firstly looked what was available in the way of books. Lots of the publications are well out of date and offer little help but I found one that was very helpful, John C. Payne's, "The Marine Electrical and Electronics Bible" which gives plumbing info as well. There are several web sites with a lot of technical information and design suggestions, www.outbackmarine.com.au and www.victron.com are 2 of many.
Once the information is digested the first step in the process was to formulate an equipment schedule listing and locating all the electrical load items in the different categories.
Form the Outback Marine site I down loaded a Load Analysis system, which I then translated into an MS Excel worksheet, which can be found at Load Analysis worksheet.
In my analysis I concluded that the equipment selection as Equipment Schedule worksheet could be provided for by the alternators in conjunction with the solar panels and the wind/water generator I had in mind. John Payne also provides an analysis method and a cursory check in accordance with his system confirmed my selections.
I decided to make my purchasing/installation progressive, at launch the boat was equipped with 2# 85 Amp alternators and 2 80 Watt solar panels on the targa. Additional solar panels and the Wind/Water generator (Duogen) can be installed based on established need after the first years sailing.
Once the loads are established and a strategy is in place for the power generation the next thing to be decided is the management system and this is where the big expense items will come in.
I opted to go for a system with an inverter/charger at its heart, as I liked the idea of seamless management of AC power input sources (shore or generator), using the excess to charge whilst making up AC shortfalls when they occur from the batteries. This allows for all sorts of future options
Batteries - The house bank, 500 AH, is made up out of 5 # 100 AH sealed no maintenance deep cycle units. The engine cranking battery is the same as is the winch (Halyard & Anchor) battery, which also serves as the engine reserve unit.
Distribution Boards - The supply boards have been separated into:
Navigation - 12 Circuits / Breakers located at the nav station. This is a BEP unit with a digital volt/amp meter
House - 30 Circuit / Breaker located at the electrical cupboard in the Port mid level passage. Domestic unit & breakers
AC Supply - 6 Circuits / Breakers, in the electrical cupboard. Doestic unit & breakers.
Inverter / Charger - Xantrex PS2212E. To provide for an air conditioning option I selected a 240 Volt 2200 Watt inverter / 100 Amp Charger. The advantage of this unit is that it will regulate the AC inputs from shore or generator supply automatically without me needing to switch from the inverter to the alternative. In addition the unit will supplement the shore/generator supply from the batteries if required. Another plus is that the unit is big enough to boil a kettle.
Smart Regulator - Ample Power. Is a must to provide for sound charging of the batteries.
Solar Charge regulator - Xantrex C40. The unit I selected is capable of managing multiple solar panels and the water/wind generator.
Electric winches - Besides an electric anchor winch I decided to also have the main halyard winch electric, just in case the RCB batcars are not as good as everybody claims they are.
AC Power 240 Volt - A good supply of mains power provides options that would otherwise be missed, like a washing machine, microwave, power tools and also enable luxuries such as, kettles (fast cup of coffee) and other kitchen appliances.
Gas Detection / Switch - BEP detector Ouyen solenoid. With the galley in the SB hull as well as sleeping quarters I decided that a gas detection/switch system was an essential safety feature. Subsequently it made it easy to provide for the gas/electric hot water unit in the engine compartment as the gas authorities approved the location subject to a detector being located in that space as well.
Future Options - As mentioned before the equipment was sized to provide for a small reverse cycle AC unit, portable generator, desalinator and more generating options.
During the build phase I decided to only partially implement the energy generation component and to wait and see how the real live conditions stack up during the first year before I embark on cruising
Alternators -The engine alternators are likely to be the main source of power, especially since they have had to be upgraded to Bosch 85 Amp units in lieu of the 55 Amp Hitachi's supplied with the Yanmars. Initially I was going to defer the upgrade but the Hitachi's are negative polarity and won't work with the Ample Power Smart Regulator.
Solar Panels - Kyocera 80 Watt x 2# fitted to the rear of the targa, I figured that there would be minimal shadow cast by the main sail in this position. The optional units on the rear of the cabin top will be 2# Canon Unisolars as they are shade tolerant.
Deferred - Water/Wind Generator - The unit I have in mind is the DuoGen made by Eclectic Energy in Great Britain. For cruising I think this unit will be essential as it will contribute the equivalent of an alternator.
Deferred - 1 KW Petrol generator. Essential if I wish to contemplate reverse cycle AC, it will also be a back up if all else fails.
After reading the books and doing the load analysis I thought I had all the problems solved until I tried to lay it out in a circuit diagram. I could not satisfy myself that the battery connections made sense or that it would work satisfactorily.
In the first instance I tried to find a marine electrician, but gave up after interviewing two of them who wanted to treat the installation like a car, no smart chargers, waste of time, no 240 V unless you start the gennie etc..
In discussing my plight with one of the suppliers he referred me to a local marine electrician I hadn't come across before, Kerrin Edmonds - Complete Marine Electrical . After I contacted him he came up, looked at the boat and we found we talked the same language. He agreed to let me do the basics myself, after which he'd come in and test/finish it.
During the first meeting he did a few sketches outlining his interpretation of my requirements, which I then used to draw up the first draught of the Circuit Diagram.
I had 2 further meetings with Kerrin during which he clarified/corrected my interpretations of his advise. This process cleared up all my outstanding doubts and resulted in my clear understanding of what needed to be done.
It is not intended that readers use the above diagram for their own installations as these are bound to be different in several key ways, any of which could effect the balance/applicability of the system. The diagram is provided to give the reader an understanding of how I tackled the subject and also provides the basis of the subsequent worksheets in the Analysis. A more detailed copy can be found by clicking the image of the Circuit diagram and then enlarging it.
In the Wiring Analysis spreadsheet there are some worksheets that deal with wire sizes and quantities, which are in-complete and have mistakes in them as I abandoned them once they'd served their purpose. I include them to illustrate how I tackled the problem.
In the installation there are 4 types of wiring:
The main cables, these are battery cable 66 mm2 and 27 mm2 as these are not tinned I had to take particular care to insulate the copper from the elements.
Tinned copper multistrand 2 core (A,N) wire, 1.00 mm2 , 1.89 mm2 and 4.59 mm2.
AC wiring, I used 1.5 mm2 3 core (A,N,E) for all but the shore connection (2.5 mm2) I also banded the wire with red insulation tape to clearly differentiate it from DC wire.
Instrumentation wiring, mostly small diameter provided with some of the equipment.
Planning the wire/cable routes posed quite a few problems, as I had no real understanding of what details I'd adopt for the furniture etc. I did however realise there was the potential for major forward>aft routes by utilising the space provided by:
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The space under the hampers which is too narrow for any other use |
Where the bridgedeck starts to slope down and a panel is used to level the floor |
Under the cockpit seats, I introduced a false level bottom with space under |
At the forward and rear bulkheads space is available for service runs, these do need to be put in early or run in conduits as later access is very restricted if not impossible.
The interior abaft (across) routing posed more problems and I solved these by:
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Running flexible conduits under the soles in locations where needed |
Utilising the space behind the headrest of the settee. This proved to be a real asset |
Introduced a sill along the cabin BH door bottom |
Having established the possible routes I could estimate the distances in order to calculate the wire sizes. I found that the distances in a F41 can dictate substantial wire sizes for what I'd consider to be minor loads, like 4.59 mm2 for the mast tricolor 25 watt globe. It may have been more economical to go for a mix of 12 and 24 volt, but I decided I did not want the complications associated with mixed voltages in the system.
When running the wires I found I had misjudged the lengths as I had only provided for straight and vertical distances between objects, the reality is that one has to dodge around to get between points, so a loading of 10 -15% should probably have been applied to the distances.
I decided to go with circuit breakers in lieu of fuses with separate switches as these offered a ready-made solution and opted for three groups:
Navigation Distribution Board - Located in the console at the nav desk it controls all the circuits that are associated passaging and electronic instruments. As these will require daily switching I opted for a BEP breaker panel with a digital DC meter that will give me the voltages for the 3 battery groups, Amps being charged/withdrawn, charge status and %.
AC Distribution Board - A standard domestic version located in the electrical compartment in a separate area in order to keep the AC and DC cables apart as much as possible. It's the small board in the top right corner.
DC Distribution Board - Again this is a standard domestic product as the circuit breakers are well protected and will rarely be switched.
The sizing of the circuit breakers took the appliance into consideration as well as the size of the wire, especially where a long run dictated a heavy wire. In these cases I used CB's smaller than dictate by the wire size. This is the board in the bottom left of the compartment.
During my original budgeting I had costed the major equipment I identified by reading the Outback Marine web site articles. I am glad I costed some of the fancy items like the DC control panel as these subsequently provided the funds for the more mundane items not included, like battery cable. The original listing can be found in the "Cost Control".xls workbook.
Once I had finalised my layouts and equipment I was in a position to do a far more accurate take off, which is included in the Electrical costing workbook. This sheet was based on the current analysis and proved to be far more accurate, as can be ascertained by comparing it with the Actual Cost column in the Cost Control workbook.
The costing in the electrical component consist of readily identifiable big ticket items, cable and a considerable amount of "sundries" (I guess 25% of the total) to make it work.
Cable Installation & Terminations
From discussion with the electrician I learned that most of the major cable terminations occur on busbars and that several would be required. He also suggested I purpose make my own out of copper strip. The required cross section was not readily available so I used brass in lieu, with stainless bolts, washers and nuts.
My first step was to finalise the equipment layout and spacing inside the electrical control cabinet and in doing so I decided to group the switches and main fuse in a purpose made panel.
Having determined the equipment layout now helped me position the busbars on the rear of the panel. A big advantage of this arrangement is that all the major cable and terminations are readily accessible in the space behind the settee.
The major cables (I my case 27 and 70 mm2 or 4 and OO AWG) require special terminating procedure, even more so in my case because I opted not to use tinned cable.
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The insulation casing needs to be stripped square & carefully |
The cable lug is then crimped on with a special tool, soldering will not do as these connections may heat up |
I then filled the end of the lug with petroleum jelly after which it was wrapped with electrical tape. |
I ran the main cable by terminating the remote end first, running the cable to determine the length, cutting it and then terminating the busbar end. Working this way I largely avoided the need to do this work in confined quarters. I also labelled the cable ends indicating their function.
The new alternators were fitted and the cables (70 mm2) to it are the major cables in the engine compartment. The starter motor ones are 27 mm2.
After the main cables were completed all the House DC services were run in and labelled, terminated at both ends. I took care to leave sufficient cable to be able to re arrange the circuit breakers should I need to.
For most of the electrical cable connection I used the bullet connectors. This for instance is the wiring for the Port Bilge pump, shower sump and Toilet located behind the mid section forward hamper.
Once the cabling was complete and terminated I bundled the wires with cable ties, which subsequently had to be un-done when I re grouped the circuit breakers to isolate those that should never be turned off (Bilge / Smart Regulator / Gas detector etc.)
In hindsight I'd better prepare the cable entry/exit provisions, some of the routes I had were to hard to get at.
At
the navigation desk, fwd SB side of the saloon I opted for a console to
arrange the equipment & provide for future expansion. What I did not
realise was the separation requirements the different component have and
these undermined my expansion plans somewhat. The VHF radio and Autopilot
were the main culprits.
Despite
my best efforts the wiring to the components ended up being a tangled
mess and it was my labelling that saved the day on several occasions.
For accessibility wires need to have plenty of length. The wiring feeds
up from the traverse duct that runs above the settee, which in turn connects
to the fore/aft duct that runs at floor level.
In
the photo ont the right at the top the wiring can be seen entering the
console, normally hidden by the removable
nav desk compartment shelve.
For functional reasons I added a remote switch for the inverter, so as to be able to control it without accessing the electrical enclosure (the inverter has a pronounced hum and I like to turn it off when not needed).
Both helm stations attract quite a bit of
installation behind them. The SB helm has the primary instrument clutch
(GPS/Fishfinder - Autopilot display - Wind - Log - Depth), an external
switch panel for externally controlled equipment, the steering hydraulics
and finally the water supply/ drain for the washing machine.
Providing access for future maintenance was a challenge set aside for the furniture installation.
The space behind the Port station accommodates the Autopilot pump & controller, steering hydraulics, some instrumentation and the bilge discharge lines/valves. It is also a major cable route so full height access had to be provided.
The main house bank, 5 # 100 AH sealed batteries, is contained in a purpose made ply/fibreglass box under the settee. The batteries are separated by 25 mm styrene foam and strapped down by webbing.
Removal of the seat base allows for removal. Battery and electrical equipment are in separated, vented enclosures.
The winch battery (halyard & anchor)
is located next to the saloon bulkhead door. The installation was done
after disassembly of the furniture and whilst access is available for
maintenance I wouldn't like to have to rewire it.
The main switch and circuit breakers are located in the bottom of the drinks cupboard and are covered by the door when shut
Both the main halyard and the anchor winch
have similar circuits, except that the main is 2 speed and the anchor
is forward / reverse. Both utilise solenoids to control the
motors.
This is the main halyard winch / console, the footswitches are located on the bottom and the open compartment are for rope storage. The winch controls, the main halyard, topping lift (spare MH), 2 reefing lines and the outhaul.
As the manufactures, Refrigeration Research, are local, I had access to information from an early stage. They offer a 240V compressor package with inverter and SS compartments, also the one compressor can serve both the freezer and refrigerator.
Performance data also suggested efficient operation electrically. The small inverter would also be useful to power small 240V loads such as battery chargers and laptop adaptors
I did at first not realise the complications associated with the deal, as they do not supply the lids/door for the compartments. These are a problem as efficient operation relies on a good seal far more than thick insulation especially in a vertical stack like mine. I solved the problem by obtaining a non working 2 nd hand fridge and modifying the doors.
The compartments were build in, in two stages. The freezer, lower compartment followed by the fridge compartment on top.
I had been warned about the terrific forces in expansion associated with the expanding polyurethane foam and braced for that. I did not consider, flotation, which it duly did and I had to sit on it to hold it down. Also unless poured in small sections shrinkage is another problem, I poured the freezer section in one height and it pulled the sides of the panelling in after it set.
After the freezer section I spend more time preparing, the door/lid jambs, and also put a bond breaker liner in to avoid the panelling getting distorted.
The fridgecompartment was then insulated in 4 pours
The shelves were again salvaged from the
old fridge, modified and newly powder coated. New seals were made up for
the door.
This is an overhead view of the drinks bin, accessible from the saloon. I reasoned this will reduce the front opening door (in efficient but convenient) being used as much. The cabin side does restrict vision somewhat but we have found we can find the drinks we're after ok.
- Not having exposure to cruising or people doing it, I decided by myself, in discussion with the boss, what was desirable. Time will tell whether we got it right, but it will be too hard to change by then and I should have taken time out to seek them out.
- I can't stress the importance of finding a good marine electrician (who doesn't think it's a car) to work with. Our arrangement, me doing the installation and him the testing/commissioning worked well, resolved all my outstanding design issues and led to what I think will be well functioning system. Time will tell.
- I'd buy commercially made fridge/freezer compartments with good door/lids/seals.
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