Battery charging

[Pipenslippers]

Hi Im a bit confused as Ive been told not to use my expensive engine for charging batteries and to use a generator when not cruising. I have a charger inverter so dont really need an inverter generator, what do people suggest I do? Use the engine or buy a cheap generator?

Ive also been informed that I need to adjust the input amps on the inverter if I wish to use a cheap generator.

Many thanks

[Rob-M]

Welcome to the forum. My suggestion would be to go boating and whilst you are boating along enjoying yourself the batteries will be getting charged at the same.

[Paul C]

Just use the engine.

[Pipenslippers]

Thanks for the reply, Im a liveaboard so just cruising isnt enough for full time use. I was told by a surveyor its an expensive way to charge batteries by using the engine when not moving, but dont really fancy using a noisy generator.

[Paul C]

I think you need to do the sums to work out which is cheaper. The generator runs on (well 99.9% do) petrol which after tax is going to be around twice as costly. And the engine can generate heat to heat water (and maybe space) too. Then there's the capital cost of the generator, storage of petrol somewhere, and its replacement cost if/when its stolen.

[peterboat]

Hi Im a bit confused as Ive been told not to use my expensive engine for charging batteries and to use a generator when not cruising. I have a charger inverter so dont really need an inverter generator, what do people suggest I do? Use the engine or buy a cheap generator?

Ive also been informed that I need to adjust the input amps on the inverter if I wish to use a cheap generator.

Many thanks

Solar panels are the way forward, often cheaper than generators, and most certainly quieter, and use the engine in winter

[Alan de Enfield]

Why do you believe that you do not need an Inverter generator (because you have a charger inverter) ?

You may find problems with the charger working if you have a poor / rough mains supply from a cheap generator, an inverter generator gives you a 'smooth' (like the mains) supply

[BruceinSanity]

What sort of engine do you have? Most modern beasts will charge your batteries quite happily as long as you run them a bit over tickover.

[Arthur Brown]

Modern engines will charge the battery easily and safely, having a generator will incur the problems of having petrol on board, plus generators get stolen more often than boat engines.

 

Solar panels are ace in summer but you need a lot to satisfy winter needs.

 

Using the engine will usually provide hot water also, so two good reasons to use the engine.

[peterboat]

Modern engines will charge the battery easily and safely, having a generator will incur the problems of having petrol on board, plus generators get stolen more often than boat engines.

 

Solar panels are ace in summer but you need a lot to satisfy winter needs.

 

Using the engine will usually provide hot water also, so two good reasons to use the engine.

Sorry Arthur, but money spent on solar is well spent, for 3/4 of the year it works. For the other 1/4 use the engine then as a plus you get hot water. why knock up thousands of engine hours and waste a load of money on diesel

[by'eck]

Hi Im a bit confused as Ive been told not to use my expensive engine for charging batteries and to use a generator when not cruising. I have a charger inverter so dont really need an inverter generator, what do people suggest I do? Use the engine or buy a cheap generator?

Ive also been informed that I need to adjust the input amps on the inverter if I wish to use a cheap generator.

Many thanks

 

An inverter/generator is an entirely different beast from a charger/inverter (Combi). The former usually running on petrol or propane (if converted), produces 240 volts AC much like other generators used on boats. A Combi takes in AC mains from shore power or generator to charge the batteries and supply onboard AC devices. When there is no external AC supply available, its inverter can take battery power to produce 240 volts AC. Hopefully you can see from this description they have entirely different roles and one cannot compensate for the other - you need both.

 

If the generator you choose hasn't a high enough power output it may not be able to run the charger part of your Combi, hence the advice given to you regarding reducing the chargers power requirement to match - a facility that is available on some but not all Combi's.

 

If you can provide the make and model (spec.) of your Combi it will be possible to advise on minimum generator power required.

[Pipenslippers]

An inverter/generator is an entirely different beast from a charger/inverter (Combi). The former usually running on petrol or propane (if converted), produces 240 volts AC much like other generators used on boats. A Combi takes in AC mains from shore power or generator to charge the batteries and supply onboard AC devices. When there is no external AC supply available, its inverter can take battery power to produce 240 volts AC. Hopefully you can see from this description they have entirely different roles and one cannot compensate for the other - you need both.

 

If the generator you choose hasn't a high enough power output it may not be able to run the charger part of your Combi, hence the advice given to you regarding reducing the chargers power requirement to match - a facility that is available on some but not all Combi's.

 

If you can provide the make and model (spec.) of your Combi it will be possible to advise on minimum generator power required.

 

Thanks, I have Victron combi 3kw, the engine is an isuzu.

So with solar panels, where would I run the cable from the controller to the batteries? To the middle battery? What amp cable would you recommend?

Thanks

[peterboat]

Thanks, I have Victron combi 3kw, the engine is an isuzu.

So with solar panels, where would I run the cable from the controller to the batteries? To the middle battery? What amp cable would you recommend?

Thanks

There are lots of threads on here about solar panels. However does your victron combi have solar panel connections? If it does then the connections from the panels would go to it. If it doesnt the cables from the panels to the controller are normally 4mm the cables from the controller to batteries may have to be larger depending how many panels etc As I say have a look at the Threads on here first then we can go from there

Peter

[Robbo]

One method is using something like the Travel Power, this a alternator/inverter on the engine. As tanagers over a portable generator is the convenience of it. Solar is good for summer but if living aboard in winter then dragging a portable genny out to just charge the battery's rather than "flipping a switch" sounds like a real chore.

 

PS. Got right thread this time!

[by'eck]

Thanks, I have Victron combi 3kw, the engine is an isuzu.

So with solar panels, where would I run the cable from the controller to the batteries? To the middle battery? What amp cable would you recommend?

Thanks

 

Thanks for info, unfortunately you missed out the Combi's charger spec. Given the inverter size though it would be typically matched to a 100 or 120 amp battery charger. If you decide to buy a generator to power it, you would need one in the 2000 - 2500 watt continuous range, to allow the charger to run unlimited.

 

If you decide on solar, the mppt controller would feed the batteries via a suitable fuse. Physical connections would depend on existing setup, but essentially to the same points that you presently draw battery power from, assuming they have been wired correctly . The size of cable and fuse would depend on the max current your controller could supply given the output and number of solar panels used, plus the distance from controller to batteries.

[peterboat]

One method is using something like the Travel Power, this a alternator/inverter on the engine. As tanagers over a portable generator is the convenience of it. Solar is good for summer but if living aboard in winter then dragging a portable genny out to just charge the battery's rather than "flipping a switch" sounds like a real chore.

 

PS. Got right thread this time!

I agree which is why I have the wispergen plus it means I have 3 methods of creating power Plus the wispergen runs the central heating and makes hot water for me its an integrated system

[Loafer]

Hi Im a bit confused as Ive been told not to use my expensive engine for charging batteries and to use a generator when not cruising. I have a charger inverter so dont really need an inverter generator, what do people suggest I do? Use the engine or buy a cheap generator?

Ive also been informed that I need to adjust the input amps on the inverter if I wish to use a cheap generator.

Many thanks

 

It won't harm your engine for a while, especially if you run it at about 1/4 throttle. No more than that, because it annoys everyone else in your county.

 

Meanwhile, take some time to learn the basics of boat electrics (google it - lots of good books, notably by Nigel Calder, I believe). Talk to other boaters, particularly liveaboards who don't use marinas, about how they do it. Also get a solar panel installation. Don't rush that one, find out how much power you need first.

 

Get a battery monitoring system so that you don't over-discharge, OR under-charge them. The 'Smartgauge' is a good one to buy if your electrical knowledge is towards minimums.

 

Try and stick to the terms of your license and restrict static power generation to the hours of 0800-2000. Even better, 1000-1700!

[Robbo]

Although Nigel Calder's book is excellent and well recommended it is quite indepth. Victron do a free book which is worth a read also.... https://www.victronenergy.com/upload/documents/Book-Energy-Unlimited-EN.pdf

[smileypete]

Some combis allow the input power to be dialled down, but as peterboat mentions, solar is well worth having.

[Loafer]

Although Nigel Calder's book is excellent and well recommended it is quite indepth. Victron do a free book which is worth a read also.... https://www.victronenergy.com/upload/documents/Book-Energy-Unlimited-EN.pdf

 

The Victron pdf jumps straight into tech-speak though, not for the uninitiated. It also assumes you have, or are going to have, a Victron battery monitor and talks only in terms of amp-hours. That is only my opinion after only reading the introduction on about page 12.

 

I am always amazed by the number of boaters who know absolutely nothing about DC power and related matters, who daren't use any power because they keep needing new batteries, but when you try to explain, it causes blank looks and a brain failure.

 

It's no problem if you have spare cash, but if not, then one needs to learn about volts and amps.

[peterboat]

Some combis allow the input power to be dialled down, but as peterboat mentions, solar is well worth having.

It is, today not a particularly sunny day I have had my autowasher on and I am doing the normal boat stuff without any power issues no gennie running or engine running a big saving in my books on wear and tear plus fuel

[Scooby]

Fill the roof with solar and use the engine for the rest of charging. No need for a genny. I have one and since I got more solar I haven't used the genny. Get between 500 watts and a 1000 and you won't worry about power anymore apart from 2-3 months in the winter which will need a little more engine use.

[Robbo]

 

The Victron pdf jumps straight into tech-speak though, not for the uninitiated. It also assumes you have, or are going to have, a Victron battery monitor and talks only in terms of amp-hours. That is only my opinion after only reading the introduction on about page 12.

 

I am always amazed by the number of boaters who know absolutely nothing about DC power and related matters, who daren't use any power because they keep needing new batteries, but when you try to explain, it causes blank looks and a brain failure.

 

It's no problem if you have spare cash, but if not, then one needs to learn about volts and amps.

It does explain the difference amps, ah's and volts for a beginner point of view. (Although it does seem daft having it in the middle if the book!) It may go into their devices but that's quite relevant for the OP. Edited March 30, 2016 by Robbo

[Pipenslippers]

Thanks for all replies, took your advice n ordered solar panels, just need to get a monitor for battery charger now to get an idea of how much the solar is charging. Have read the vitron manual already.

Any tips on cheaper battery monitors? Cheers

[peterboat]

Thanks for all replies, took your advice n ordered solar panels, just need to get a monitor for battery charger now to get an idea of how much the solar is charging. Have read the vitron manual already.

Any tips on cheaper battery monitors? Cheers

To keep it simple the non tech way is the smartguage lots on here swear by them. I needed to know how many amps I was creating/using so went for a NASA BM2, which was roughly the same price as the smartguage. Now it is up to you to study the threads on here and make your own mind up as it really does depend on what information you require as to what device you fit

Edited March 30, 2016 by peterboat