Inverter or Generator?????

[EchoBeach]

Hi techno buffs - could anyone out there recommend the use of either inverter or generator? How quickly will the battery drain when using a 1500W intverter at max capacity. Also is it practical to use a PC as a plotter and does it need to be linked to a GPS, if so, how?! Could a radar also be linked to the pc
Thanks

 

[Stingo]

Welcome to the forum.

It is possible to link a GPS to a computer. What sort of GPS do you have and is it conneted to an NMEA?

The drain from an inverter will depend on the size of your battery bank.

What size boat do you have?

 

[EchoBeach]

Hi! thanks for that, we are researching prior to purchasing shortly a 42 Deck Saloon. Will probably have two 110 AH batteries and are looking for the best way to provide power to teenagers gadgets! ie ps3, pc, tv etc!!
Cheers

 

[lenseman]

Hello Paul (and Sarah) welcome to the YBW forum(s).

You don't say where you live and on what type of boat you are planning to install these facilities but I will try and answer them.

Firstly, the length of time a battery will last is really dependent on its capacity or the capacity of a number of batteries all linked together.

Secondly, a 1500watt inverter will not satisfactorily give 1500watts as it will start to struggle when loaded over 1kilowatt and they are not 100% efficient. Therefore the demand on the battery(s) will be fairly large.

In regards to the PC as a plotter, well to plot a track, course, on your pc, you will need to know where you are on the surface of the water which in turn requires a GPS plot unless you are going to manually input the data you have obtained from a sextant or some other sighting (fix) into your PC.

To link a radar into a PC is really beyond the capabilities of the average person but it can be done:

http://www.si-tex.com/html/integrating_radar_with_compute.html


Finally a thought for you. If you rely on your PC for all your navigation and it goes wrong . . . . /forums/images/graemlins/confused.gif. . . it is always best to keep separate if you can so that if one unit 'dies' you still have backups.

I wonder where you are located?

I hope this helps?

 

[EchoBeach]

Hi David! Thanks that's great - we're currently researching prior to purchasing a 42 DS for med cruising. I wondered if it would be possible to utilise the PC we are taking with us instead of buying a separate plotter or radar - any advice/suggestions. We are uk based. Up to press we need the power to run teenage sons gadgets ie playstation, tv, but hoping they'll soon be redundant once we're on our way! The pc we have is a Sony Vaio MultiMedia wireless system rated at 1.9 amps.
Regards Paul

 

[HenryB]

Hi Paul and Sarah,

Ignoring losses (due to inefficiencies in the device) the process of drawing 1500 Watts from an inverter will require a current of at least 117 amps (watts=volts x amps). A reasonably sized deep cycle battery will have a nominal capacity of around 120 amp hours, but in practice it is unwise to deplete the battery by more than 50% of its nominal capacity, so only 60 amp hours are available. Therefore, starting from a fully charged battery you could draw 1500 watts for about 30 minutes. Build up a battery bank of 4 x 120 amp hour batteries and you would extend that time to about 2 hours. However, you would then need to recharge those batteries somehow - so, I would say, if you intend to use 1500 watts on a regular basis for any length of time you will be better off using a generator.

PCs make very good chart plotters and can use cheap USB GPS units but my experience of them is very limited so I'll let a more informed member answer that one.

As Stingo said, Welcome to the forum.

Henry

 

[lenseman]

Well, you don't 'need' a Radar. A large number of liveaboards do without this item quite satisfactorily, they are really a luxury which would be nice to have. How often will you be on night passage and how often will you be sailing in fog? /forums/images/graemlins/confused.gif

Night passage requires very, very good watch-keeping. A radar, once you have looked at the PPI (screen) [PPI = Plan Position Indicator] will blind your night-vision so you will need two crew on watch, one below looking at the Radar and on on deck using mark one eyeball technology. Just out of interest, when I was in the Royal Navy it was a punishable offence to have been in a lit area (unless lit by a 'police light' which was dull red in colour) within 45 minutes of your watch-keeping. It takes that long for your eyes to be 'fully' acclimatised to the darkness of the night.

To all intent and purposes, a computer screen will destroy your night vision. You would get about 60% back within 10-15 minutes but you would not be able to see properly for 45 minutes and that isn't considered safe!

An inverter is quiet whereas a generator will make a noise which always seems worse after dark and running a genny on a pontoon after 8 or 9pm at night will win you no friends. Remember a large percentage of liveaboards want to get away from all the technology and the rat-race and that includes 'noise' /forums/images/graemlins/shocked.gif

I would personally start with Imray charts and a hand held GPS (Garmin 72) and learn to plot and fix every ½-hour to 1-hour.

Playstations and sea water (salt spray) are not good bed-fellows and it might be wiser to apply some psychology and get the lads to help and get them fully involved with deck duties (furling and reefing) and weighing anchor etc.You can assign one as the pilot/navigator and task him to write down the hourly GPS reading in the log!

Contact me if I can be of further assistance

 

[Pincoya]

We live aboard our Island Packet 44 and have a 2Kw inverter fitted, including a three phase battery charger. We have two group 8D AGM house batteries with a total capacity of 550 Ah. We have two 130W solar panels and added a 2kw honda generator to our inventory so that we did not need to run our engine when at anchor.

Do not underestimate the amount of power you will use if you wish to be comfortable, we do not use air con, except when on shore power, and do not run mains operated equipment as a rule. Even so, we need to re-charge about every third day.

You might also want to consider installing a nanopulser PG-12N too.

I'm not saying we are the way to go, but it works for us.

Paul

 

[Forbsie]

If I were you, I would buy a colour GPS/Chartplotter and put a PS6 sticker on it!

Then all you need to do is say "Son, I'm having a lot of problems understanding this technology. Can you give me a hand?" /forums/images/graemlins/grin.gif

Sort of tongue-in-cheek but I'm sure that he would enjoy the experience more if he was involved and 'relied' upon.

 

[EchoBeach]

Thanks guys for all your advice - we're really impressed! I'm sure the gadgets (Playstion etc)will soon be forgotten about, however up to press they appear to be swinging it (bribery) "to go or not to go". I'm sailing out of Largs over to NIreland this week so won't be on the forum. In the meantime thank you very much for all your invaluable advice. Best regards, Paul

 

[ShaunG]

Paul and Sarah,

Onboard PC's are an area that i specialise in so i will answer best as possible from experiance.

There are a number of PC's and associated software that will allow chartplotting and radar to be carried out.

The PC's are normally ITX based and can be powered directly from 12v, they are low power and more efficent than a laptop, the PC's are usually used with a TFT monitor and wireless keyboard and mouse.

The PC's are installed with a Chartplotting software package, Seapro 3000 or Nobletect VNS are but two of the software options that allow you to link a radar directly to the PC

With regards to obtaining GPS position data this is achieved by taking the NMEA output from the GPS and plugging it in to the PC by a serial port ( its 3 wires to be soldered on to a plug) Most people have a normal marine GPS (garmin) so that in the event of PC failure they still have a GPS position to help them with navigation.

The Radars for Seapro 3000 and Nobletec VNS are designed to work with the software and they connect to the PC using USB ( there is no external display) The radar is controlled from the PC application and can be overlayed directly on the chart

If you would like more info or wish to discuss further then please feel free to PM me

ShaunG

 

[ccscott49]

OK, Welcome to the forum!

you are in a similar position, almost, as myself.

I run mains equipment on board, with an inverter, I have a 3000w pure sine wave inverter, you do not need one this size, because I also use mine to start and run a 95 LPH, watermaker when motoring. A 1500w pure sine wave inverter will be plenty adequate, theres a couple or fifty for sale on E bay at the moment.

I have a 320w solar array at 24v. This means I need to charge my batteries about every 2-3 days at anchor, I do not drain my batteries by more than 30-40% (440 ah. @ 24volts) this ensures they are kept in tip top condition and they last.

I have a 4.5 kw genny and would reccomend you also have a generator, you can have a small suicase type, honda or whatever, 2kw and quiet! This will allow you to run all your bells and whistles, of course when you are sailing/passage making you will need to be charging batteries, and in the meddy you will be doing a lot of motoring anyway.

When I charge my batteries, I also run my watermaker and washing machine, as the charger is using 1200w from the genny so I have ample power to do all the other things. Need less to say I do not need to make water or run the washing machine every three days, but once a wee or so. I have found laundry in the meddy to be very expensive!

Chart ploting on the computer is easy and available, you can purchase a waterproof USB puck type gps for less than 50 quid again on E bay, then the choice of electronic charts and software is up to you. I dont know anything about radar on computer, mine is a free standing unit.

I would also reccomend the largest battery bank you can fit and charge effectively with genny and engine alternator, I also reccomend a "smart regulator" for your alternator and a 3-4 stage mains charger.

None of this stuff has to be expensive, using E bay and other sites, I have picked up most of my stuff for less than 25% of new cost! In some cases, a 5500 pound watermaker for 500!

I am in the meddy and spend at east six months of the year at anchor, this works for me.

Lemain would be a guy to ask also.

If you need to know more, PM me.

 

[Anonymous]

Hi, Welcome to the forum /forums/images/graemlins/smile.gif

My setup is very similar to Englander's - large solar panels, diesel generator and the largest 'semi-traction' battery bank I could fit in the box (3 x 180 Ah = 540 Ah at 12V). My batteries are rated for a 5 hour discharge (most don't like to be discharged too fast) and at a 5 hour rate that you would think would give 108 Amps max continuous discharge - BUT NO!!!! - Also written on the batteries is the fact that while the individual battery size is 180Ah at a 20 hour rate you only get 135 Ahr at the 5 hour rate. So, at a 5 hour rate we would have only 3 x 135 Ah = 405 Ah. 405 Ah at a 5 hour rate gives a discharge rate of only 81A.

As Englander said, you don't want to discharge your batteries too far....I use 2/3 as a daily target and never go below 1/2. So in my case, I could power an inverter at 81A for around 2.5 hours - but that would be it, no fridge, lights, pumps, etc. The terminal voltage doing this would be a bit less than 12V and given the inefficiency in the inverter, that would give a maximum power out of about 850W to 900W. So in my case there would be no point in having more than a 1kW inverter. Actually I have a 600W inverter and it seldom runs anything more than 100W other than for very short periods (small hairdryer). Any more than that and I run the genny - it is a 6.5 kVA fixed diesel genny and all you have to do is turn it on, no messing about.

Definitely get a pure sine wave inverter. Some equipment can blow up on modified sine inverters - most things are safe, many things don't work well, and a few things blow up and you will have no come-back on the manufacturer when your laptop or TV blow up. They are much more expensive and they are bigger but I advise you not to be tempted unless you are only going to run lights and vibrators. Square wave is particularly suitable for the latter /forums/images/graemlins/wink.gif

I am no fan of using energy stored in batteries to do things like heating and cooking, it seems such a waste when that can be done better with gas or by running the generator - other than the hairdryer which for us is a special case, as we don't like to be without it and on low setting it 'only' draws 500W and then only for five minutes. Charging batteries is not an energy-efficient exercise (though solar and wind are free, of course) and they are lifed items. All batteries have a maximum number of charge-discharge cycles. They seem to last far longer if you never take them below 50% capacity and if you don't stress the plates by overdischarging too often - though traction, semi-traction and engine start batteries are designed to handle high currents for some time.

If you are living aboard in warmer climates or for longer passages running the engine, I would recommend 'flooded lead acid' batteries - i.e. the type you can top up. Some people seem to have done very well with sealed batteries but the previous owner of my boat had terrible trouble and I know other who have had trouble as well. If you can top them up you can always add water and no harm is done.

Enjoy your life aboard and make the most of this forum - there is a huge amount of knowledge here and one of the big benefits is that if someone tells you something that is either plain wrong or there are differences of opinion, others will drop in an tell you. Ask a question about anchors here, and you will find that out /forums/images/graemlins/smile.gif

 

[Bejasus]

Hi Paul, and welcome
We moved aboard last October on a boat we bought in the US and our set up(came with the boat), is as follows.

2 x Rolls marine battery bank = 820 amps
1 x Group 27 engine cranking battery
90 amp Balmar alternator w/ smart regulator
2 x 110w Seimens solar panels
1 x 4.5 kva Entec diesel generator
1 x 2500w Xantrex modified sine wave invertor/3 stage charger(not perfect sine wave I know)
3 stage battery charger
1 x Heart interface controlling all of this.

not having studied exactly what our output at anchor would be, this is what we would have running

1 x 12v galley fridge
1 x 12v freezer
normal lighting requirements
12v cooling fans if required
a/c which would only be run if generator running(or on shore power)
small washing machine, yet to be purchased(running maybe once per week)
We have another fridge/icemaker which can be run off the invertor
1 x Ocean PC with GPS input running Maptech's 'The Cap'n' plotter software and Ocens Weather software
SSB & VHF, TV/DVD player when wanted
Radar, but not on PC(anyhow, how much do you use it)
Garmin chartplotter/fishfinder at the helm
Powerflush heads(only used when required /forums/images/graemlins/smile.gif)
12gph watermaker, which I haven't used yet.

We so far have been very, very comfortable with all of this, but as stated earlier, we haven't spent any time at anchor yet, although 3 day sails have seen no problems with any of this stuff. All of our mains power is 110v so when we come to the EU next year I will have to look at some kind of transformer.

 

[captainslarty]

Hi
An inverter to give you 1.5 Kilowatts out would be drawing around 130 amps due to inneficiencies.
Basically your proposed battery bank would not hack it. The amount of current batteries can supply for a given time is dependent on the discharge rate. you would be lucky to get 25 min.
How are you calculating that you need 1500 watts ? that is a lot of power.
A generator would make far more sense if you actually NEED that amount of power.
Joe

 

[colinroybarrett]

Dear Paul & Sarah,

You don’t mention your proposed cruising ground; so for what it is worth, our input:-

We have been based on the inland waterways of Europe for 4-and-a-bit years, our boat has no ‘sticks or rags’ so we motor everywhere; giving us plenty of hot water from the engine and battery charging through the 55-amp alternator, (standard Lucas, no intelligent charger fitted).

Freedom is very power hungry, even the ‘loo’ runs off 240-volt mains; however, we have regular access to shore power, when we feel the need to pay for it, although when not under power, we always switch the fridge back to gas as these long-term mains voltage devices are the real killers of battery power.

On the domestic side we have 2x120 batteries, but in series, as we are a 24-volt boat. Coupled to this we have a 750-watt inverter, which we use for the fridge, worktop oven, small electric kettle, television, satellite, hairdryer PC, toothbrushes etc. The heavier items are used when we are running as the amperage consumed, even for the kettle ‘clobbers’ our batteries very rapidly.

Without shore power, we last 2-3 days, watching TV, with lights etc before we need to fire up our diesel generator:- 3.5kva, which heats water via an immersion, powering the washing machine, the 3-stage battery charging system, running for about 1-1/2 hours per day, just about keeps us ‘alive’.

In conclusion inverters, are very handy, but you will need a generator to keep batteries charged at the sort of consumption you suggest, especially if you intend to sail a lot!

Best regards,
Colin & Urszula Barrett
‘Freedom’

 

[Richard10002]

[ QUOTE ]
Hi techno buffs - could anyone out there recommend the use of either inverter or generator? How quickly will the battery drain when using a 1500W intverter at max capacity. Also is it practical to use a PC as a plotter and does it need to be linked to a GPS, if so, how?! Could a radar also be linked to the pc
Thanks

[/ QUOTE ]

Paul & Sarah,

I'm living aboard with a 2000W inverter which shares its' battery, (200Ah), with the Bowthruster. It doesnt last long, and I only tend to use 240v stuff if I have the engine running, charging the batteries or, I start the engine when I want to use 240v stuff.

I also have 3 x 110AH batteries, (2 dedicated to domestics, and 1 to the engine... I dont know if the domestics use the engine battery if both banks are switched on).

I dont have a generator, (well I do, but more of that later), so I find I have to run the engine to charge the batteries for several hours a day.... which is both irritating, and probably not good for the engine, and probably not an effient use of the fuel.

On the generator... I have one from the previous owner which is still in its' plastic wrapping. I've always been reluctant to use it as it holds petrol and I'm concerned about the vapours building up given that it would be stored in a locker.

Anyway.... having responded to your query, I think I'm going to get the genny out, make a cable so it can be connected to the shore power input, and see how well it charges, and how noisy it is... So that's tomorrows job!

Inverter or Genny? I dont know yet. without the inverter you need to be running the genny to get 240v - not easy at sea, unless the genny is fixed, or it's calm. Both I guess... which doesnt help, but identifies the problem which needs solving.

On the PC as a plotter/radar. I think getting radar to a PC is a very expensive job - just something I heard, so things may have moved on.

I have a plotter capability on my laptop which sits on the saloon table and can be seen from the wheel. I USE SOB software, and C-map charts - it's excellent.... except:

Unless you have waterproof screens, your PC will be below, and you will be on deck. Any changes to the display require a remote facility, or for someone to go below and make them - inconvenient.

With this in mind, I have a Lowrance 3600i plotter fixed at the wheel so that it swivels to be seen from the wheel, or from the cockpit in front of the wheel. With Nauticpath charts, it's not that good at close quarters stuff, so I wish I had bought Navionics charts or, if buying now, I would buy a small plotter which uses C Map charts, so I could switch from laptop to plotter, (although the laptop would probably become redundant in terms of plotting). I'm thinking a small Standard Horizon plotter probably, or posibly a Navman.

If you want radar on your plotter, the best bet is to buy a brand which does both and allows you to have the plotter on deck... You cant have the PC on deck, and waterproof screens are prohibitive.

If I were buying a boat again, with the knowledge I now have, I would look for one with built in generator, inverter, solar panels, wind generater and water maker, or I would build them into my budget, and make sure the boat could accommodate them..

Hope that helps

Richard