Simple Solar For A Simpleton

[VirtualVagabond]

Originally Posted by Don Lucas

When what gets back to 14-14.2V? If I start at 12.2 and start my engine to recharge I will get to 14.4V almost right off, but that desn't mean I put any charge in. Voltage when charging only tells you that you are charging at a high enough voltage, nothing about state of charge. I've wondered about this too. The volt reading climbs quite quickly initially to around 13 or 13.25, and then slowly until it gets to around 14v, with the genny running. When I turn the genny off it immediately drops of course, and I would think that is the true level to which I have charged.

But this doesn't match the amount of time you are running your generator. You need to know the amps in to compare to your battery capacity and if possible your amp-hours in/out.

It kind of sounds that you aren't really getting your batteries charged even though you have a massive amount of generator run time.

I really have to devote some time to establishing my daily amp hour consumption. By many accounts here it appears my run time is ridiculous.

[denverd0n]

Originally Posted by VirtualVagabond

...we will be looking at reducing energy consumption later.

Big mistake. This is where you should START, not finish. The usual rule of thumb is that $1 spent reducing consumption is worth $10 spent increasing generating capacity.

Get your consumption under control and then you'll have a sane starting place for figuring out how much generating capacity, and how large of a battery bank, you really need.

[Bash]

Originally Posted by atoll

sounds like you are starting at the wrong end of the equation when working out your power needs.

+1 You have a huge battery bank, and shouldn't need one nearly that large. I have a 420 AH house bank that rarely drops below 12.6 volts, with only 270 AH of solar backed up by 200 AH wind. And that's with running separate fridge and freezer units.

Time to start thinking about efficiency. You're having to run your genset waaaaaay too much.

[foggysail]

Originally Posted by VirtualVagabond

Foggy,
Good point.
What is the calculation to get to the amp hours rating from 10 x 6v 105amp batteries?

Vic

Vic, I am confused. Why do you want to know about 105 amp batteries when your batteries are rated for 225 ampere hours?

OK, maybe you made a mistake so I will go on that assumption.

You have 10 batteries, each rated at 225 ampere hours for a total of 2250 ampere hours if you connect them all in parallel. But that is a 6vdc battery bank which is of no use to you.

So in order to make 12vdc, you have only 1125 amperes because you need 2 each 6 volt batteries connected in series to make the 12 vdc. Make sense?

Foggy


EDIT! You NEED A LARGER smart battery charger among other things. Olso I also highly recommend you purchase a decent battery hydrometer and check each of cells after you believe they are fully charged. You could have sulfated cells. Equalization might help if so.

[atoll]

as a comparison,a boat i delivered to the canary islands,about the same size as yours,having 2 fridges and a freezer,all on their own compressors averaged about 15 amps,andtotal of 18- 20 amps with the radar ,plotter and navlights.

most fridge units only draw 4-6 amps sounds like it might be an idea to find where the other 10 amp hours is going!

good point about the genset output,if the charger is rated for 240 v @50 hz,and the genset is rated for 220 v @ 50 hz,the charger will not charge correctly unless on shore power at the correct voltage.

stuff bought in south africa is 240 v,not 220v

[DeepFrz]

Disconnect that hot alternator and see how much that drops your usage.

[Dsanduril]

if the charger is rated for 240 v @50 hz,and the genset is rated for 220 v @ 50 hz,the charger will not charge correctly unless on shore power at the correct voltage.

Most electrical equipment does not care that much about exact voltage, the current just goes up or down slightly. In the US we say 120V, but the delivered nominal utility voltage can be anywhere from 110 to 115 to 117 to 120 depending on the utility and their installation, and then there is the allowed variation from the nominal on top of that. Yet there are not different versions of equipment for each of those voltages. Just the same as your chartplotter, fridge, and just about everything else on the boat will run at anything from about 12.0VDC to 14.4VDC. They're nominally rated for 12 Volts, probably designed around something between 12.6 and 13.8, and willing to accept +/- 5 to 10% of nominal voltage. Might not be as efficient at the low end, but they still run.

The Outback chargers are nominally rated for 230VAC and should be quite happy about running at 220 or 240. If not, they are adjustable, according to the manual the input AC voltage is adjustable from 160 to 300 VAC. If your genny is putting out 220V then this is probably the last place I would start to look, if it is putting out substantially less than 220 then it may be worth adjusting the charger's input voltage to match the genny output.

I'm with all the other posters, you really need to look at where all the juice is going and figure out if it is power your need to use (in which case you need to decide on your strategy) or power that is being wasted for some reason (in which case you can prioritize fixes).

[VirtualVagabond]

Originally Posted by foggysail

Vic, I am confused. Why do you want to know about 105 amp batteries when your batteries are rated for 225 ampere hours? I'm the confused one, Foggy. When I look at my batteries, they say Trojan, T-105Plus Deep Cycle. The previous owner told me they were 6v, 105 amp batteries. Was this wrong?
I don't understand where the 225 ampere hours comes from. Is 225 the battery rating and most people just know it?

OK, maybe you made a mistake so I will go on that assumption.

You have 10 batteries, each rated at 225 ampere hours for a total of 2250 ampere hours if you connect them all in parallel. But that is a 6vdc battery bank which is of no use to you.

So in order to make 12vdc, you have only 1125 amperes because you need 2 each 6 volt batteries connected in series to make the 12 vdc. Make sense?

Foggy


EDIT! You NEED A LARGER smart battery charger among other things. Olso I also highly recommend you purchase a decent battery hydrometer and check each of cells after you believe they are fully charged. You could have sulfated cells. Equalization might help if so.

The boat has an Outback FX series inverter/charger. I assume it must be the FX - E which is their model for the export market and puts out 230v /50 Hz.

Would you categorize that as a large smart battery charger?

The generator Test certificate dated 2009 shows 230v/50 Hertz and actual results 233v/50.1Hz. Battery charge system 13.57volts.

[atoll]

OutBack Power / Products / Sinewave Inverter / International

@100 amps cont charging is the rating for the fx-e 12v,sounds like the gen and charger are matched okay.

if you can ,get an ammeter switch every thing off,and turn stuff on, one at a time,(with the charger off on shore power) this will give you a better idea of high current drain from each appliance,check first there is no drain with every thing off.

a bad battery will also pull the whole system down,checking each cell with a hydometer is the only way to tell.

[jeremiason]

Originally Posted by VirtualVagabond

We also have an Outback Inv/charger. It will be their export model because we're wired for 12v DC and 230v AC. From the User Guide I can't find what the charger amp rating is. Would it be the same for all their inv/ch models or would it vary?
The boat also has a Xantrex Link 2000 that I haven't got my head around, but I use it to tell when I need to run the genny.
I don't let the reading drop below 12.2v and I charge until it reads between 14 - 14.25v

Vic

First get to know your Link 2000 Battery Monitor... If yuou don't have the manual you can download it off the web, just search "Link 2000 Manual"... There are two versions. The Link2000 will monitor your Ah consumption.

I would bet you are not burning as many Ah as you believe since you are charging at 12.25 volts, which is still very good voltage. You should be able to run your battery bank down to 11.5 volts no problem. (Again the Tech Geeks can jump in here and explain battery discharge...)

As an example for Ah, I currently run an Alder Barbour Refridgerator and an Engel Portable Freezer, both 12 volt, which combined down here in the Panama heat, burn somewhere around 8 amps an hour or about 180 amps per 24 hour day. Realistically with lights and computer I burn about 200-220 amps per day.

As for the Outback without a model number it would be difficult to fugure out what it is doing, but a quick internet search indicates it could be between 100-125 Amps, which should be more than enough.

To give you an idea of charging time, my ProSine 3.0 has a 125 Amp battery charger and takes about 4-5 hours to completely top off the battery bank when it is around 350 Ah down.

The 14 volts you are using to say the batteries are full is actually what the charger is produicing... Not what the batteries are holding. Your batteries without a load or charge going into them should measure 12.75 volts in series when full.

You can figure out how much your charge is producing by using you Link 2000, which monitors Ah currently being used, but should go positive when your battery charger is on. It will indicate how many Amps are going into the batteries. If you haven't used it in a while you should completely top you batteries off and then reset it. Once that is done you will have more of a realistic idea what is going on with your batteries.

So before you spend any money on new batteries, or anything else get your Link 2000 working to evaluate your current battery usage.

After that Solar is the way to go!

[VirtualVagabond]

Originally Posted by atoll

as a comparison,a boat i delivered to the canary islands,about the same size as yours,having 2 fridges and a freezer,all on their own compressors averaged about 15 amps,andtotal of 18- 20 amps with the radar ,plotter and navlights.

most fridge units only draw 4-6 amps sounds like it might be an idea to find where the other 10 amp hours is going! Agreed. We've got an Italian Isotherm fridge/freezer, and the compressor for the top loading fridge is a German Danfoss. I need to get online and find out what their consumption is.

good point about the genset output,if the charger is rated for 240 v @50 hz,and the genset is rated for 220 v @ 50 hz,the charger will not charge correctly unless on shore power at the correct voltage. Just checked on line, S A's official standard is 230v/50Hz, same as Europe. Growing up there everyone talked about 220v, but that was a long time ago!

stuff bought in south africa is 240 v,not 220v

It is quite clear that we are gulping energy compared to other setups, so I'm going to have to find out where and why.

By your and other accounts we should be able to run what we have with the existing battery bank, some solar panels and the generator for topping up as and when necessary.
Vic

[VirtualVagabond]

Originally Posted by DeepFrz

Disconnect that hot alternator and see how much that drops your usage.

Thanks. Makes sense. It's one of the first steps in analyzing where all the energy is going, which I now realize I have to do before going further.

[VirtualVagabond]

Originally Posted by Dsanduril

I'm with all the other posters, you really need to look at where all the juice is going and figure out if it is power your need to use (in which case you need to decide on your strategy) or power that is being wasted for some reason (in which case you can prioritize fixes).

It's actually good to know that everyone else has systems that are so much more efficient.
Now I just have to work out why mine isn't.

[atoll]

Originally Posted by jeremiason

Vic

First get to know your Link 2000 Battery Monitor... If yuou don't have the manual you can download it off the web, just search "Link 2000 Manual"... There are two versions. The Link2000 will monitor your Ah consumption.

I would bet you are not burning as many Ah as you believe since you are charging at 12.25 volts, which is still very good voltage. You should be able to run your battery bank down to 11.5 volts no problem. (Again the Tech Geeks can jump in here and explain battery discharge...)

As an example for Ah, I currently run an Alder Barbour Refridgerator and an Engel Portable Freezer, both 12 volt, which combined down here in the Panama heat, burn somewhere around 8 amps an hour or about 180 amps per 24 hour day. Realistically with lights and computer I burn about 200-220 amps per day.

As for the Outback without a model number it would be difficult to fugure out what it is doing, but a quick internet search indicates it could be between 100-125 Amps, which should be more than enough.

To give you an idea of charging time, my ProSine 3.0 has a 125 Amp battery charger and takes about 4-5 hours to completely top off the battery bank when it is around 350 Ah down.

The 14 volts you are using to say the batteries are full is actually what the charger is produicing... Not what the batteries are holding. Your batteries without a load or charge going into them should measure 12.75 volts in series when full.

You can figure out how much your charge is producing by using you Link 2000, which monitors Ah currently being used, but should go positive when your battery charger is on. It will indicate how many Amps are going into the batteries. If you haven't used it in a while you should completely top you batteries off and then reset it. Once that is done you will have more of a realistic idea what is going on with your batteries.

So before you spend any money on new batteries, or anything else get your Link 2000 working to evaluate your current battery usage.

After that Solar is the way to go!

+1 on getting to know the link 2000,which in reality is an ammeter,with a memory!

you will need to reset it to get an accurate reading for amp hours in and out.

also have a good look at the terminals on the battery bank for wiring that might have been added on at a later date,and not be drawing power via the link 2000,this can also cause false readings.

[kefroeschner]

Nice discussion, but I do wish that some of you would get the difference between amps and amp-hours figured out. Phrases like '100 amps per day' make no sense. You probably mean to say '100 amp-hours per day,' which would mean an average current of about 4 amps over 24 hours.

Please don't get offended by my quibble -- I've seen lots worse in print, but it makes more sense if you get the units right. And since we're are going electric we might as well lean the lingo.