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Post by bettina on Oct 28, 2016 12:41:24 GMT
Would a large (1k (watt?) supply, on a sunny day be able to complete the float phase? Please try to make any replies as 'non-techy' as possible. I wasn't even confident enough to use the term watt without questioning myself. I do 'get' the 3 different stages of battery charging....the AB&F's is now I remember them currently Very probably 'Yes' unless you have a huge battery bank that is very discharged. I am taking more than 1000Ah capacity. We have a bank of 8 leisure batteries and then 2 at the front for the starter & BT (which we don't use) The bit I've highlighted above is way beyond my current comprehension at present; I know Ah is Amp hours, however I don't know what an Ah actually is. But I'm getting there, I'm making my way through Tony's great posts, this one, along side the Boating terminologies, I'm sure it's more than likely covered in one of them and I'm finding them a fairly easy read, it's just a matter of retaining it all in a brain with very limited space
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Post by tonyqj on Oct 28, 2016 13:03:26 GMT
Very probably 'Yes' unless you have a huge battery bank that is very discharged. I am taking more than 1000Ah capacity. We have a bank of 8 leisure batteries and then 2 at the front for the starter & BT (which we don't use) The bit I've highlighted above is way beyond my current comprehension at present; I know Ah is Amp hours, however I don't know what an Ah actually is. But I'm getting there, I'm making my way through Tony's great posts, this one, along side the Boating terminologies, I'm sure it's more than likely covered in one of them and I'm finding them a fairly easy read, it's just a matter of retaining it all in a brain with very limited space For your purposes, think of an Ah (Amphour) as a 'unit of power'. A typical leisure battery will have 110 of them, so it's a 110Ah battery. Two batteries would give you 220Ah, three would give you 330Ah etc. So your 8 leisure batteries might give 880Ah, but it all depends on the battery - note that I said 'typical' was 110Ah; yours could be bigger or smaller. Hope that helps.
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Post by tonyb on Oct 28, 2016 13:05:33 GMT
An Amp hour (Ah) is an artificial unit designed to make it easy for non-scientists to understand how much electricity a thing like a battery can hold so a common size of boat battery is 110Ah. If we ignore some complications that will not matter much to a typical boater for most of the time then this battery can supply 110 amps for 1 hour, 1 amps for 110 hours, 55 amps for 2 hours, 25.5 amps for four hours and so on. Unfortunately from the moment the battery is filled with acid the number of Ah on the label gradually reduces and the more you abuse the battery the faster the reduction of Ah it can hold becomes. To make any use of this information you need to be able to calculate how much electricity in Ah the stuff on a boat uses and it is done in the same way. So something drawing 1 amp for 3 hours will take 3Ah from the battery, 10 amps for half an hour 5.5 Ah, 2 amps for 6 hours 12 Ah and so on. You can find out the amps something draws by dividing any wattage by 12 or 24 depending upon the boat's electrical system but that is nothing to do with what an Ah is or what it means. In real life a battery will rarely contain as many Ah as the label says, even if it is fully charged and it is not so easy for a typical boater to measure. Some of those complications I mentioned are: A battery will demand rather more Ah put back into it to get to fully charged than those taken out. Discharging at high currents (amps) reduces the Ah apparently available. Discharging at low currents will increase the Ah apparently available. Tony posted while I was typing. But for most electrical loads on most boats these last two effects can be ignored. Hope that helps.
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Post by tonyqj on Oct 28, 2016 13:06:56 GMT
An Amp hour (Ah) is an artificial unit designed to make it easy for non-scientists to understand how much electricity a thing like a battery can hold so a common size of boat battery is 1110Ah. If we ignore some complications that will not matter much to a typical boater for most of the time then this battery can supply 110 amps for 1 hour, 1 amps for 110 hours, 55 amps for 2 hours, 25.5 amps for four hours and so on. Unfortunately from the moment the battery is filled with acid the number of Ah on the label gradually reduces and the more you abuse the battery the faster the reduction of Ah it can hold becomes. To make any use of this information you need to be able to calculate how much electricity in Ah the stuff on a boat uses and it is done in the same way. So something drawing 1 amp for 3 hours will take 3Ah from the battery, 10 amps for half an hour 5.5 Ah, 2 amps for 6 hours 12 Ah and so on. You can find out the amps something draws by dividing any wattage by 12 or 24 depending upon the boat's electrical system but that is nothing to do with what an Ah is or what it means. In real life a battery will rarely contain as many Ah as the label says, even if it is fully charged and it is not so easy for a typical boater to measure. Some of those complications I mentioned are: A battery will demand rather more Ah put back into it to get to fully charged than those taken out. Discharging at high currents (amps) reduces the Ah apparently available. Discharging at low currents will increase the Ah apparently available. But for most electrical lads on most boats these last two effects can be ignored. Hope that helps. Too many 1's in your first sentence Tony 😀
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Post by tonyb on Oct 28, 2016 13:08:30 GMT
Yes just edited - and the lads further down.
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Post by Gone on Oct 28, 2016 13:21:36 GMT
We have a bank of 8 leisure batteries and then 2 at the front for the starter & BT (which we don't use) The bit I've highlighted above is way beyond my current comprehension at present; I know Ah is Amp hours, however I don't know what an Ah actually is. But I'm getting there, I'm making my way through Tony's great posts, this one, along side the Boating terminologies, I'm sure it's more than likely covered in one of them and I'm finding them a fairly easy read, it's just a matter of retaining it all in a brain with very limited space For your purposes, think of an Ah (Amphour) as a 'unit of power'. A typical leisure battery will have 110 of them, so it's a 110Ah battery. Two batteries would give you 220Ah, three would give you 330Ah etc. So your 8 leisure batteries might give 880Ah, but it all depends on the battery - note that I said 'typical' was 110Ah; yours could be bigger or smaller. Hope that helps. The battery capacity is usually written on the product label. Of course the capacity is only true when new and will reduce over time as the battery 'wears out'. It is the actual capacity of the battery that needs recharging. As to your question about what is an Ah. An AmpHour is one amp flowing continuously for one hour. So a lamp taking 1 amp turned on for an hour would use 1Ah. An inverter taking - for example - 75Amps would use 75Ah per hour, or 1.25Ah every minute. So run your microwave for 5 mins (assuming it draws 75A) and would use 5x75=375Aminutes which if you divide by 60 would give you the answer in AmpHours because there are 60 minutes in one hour, giving us 375/60=6.25Ah of battery used up. So though microwaves use a lot of power, they are not on for long. It is a little bit more complex than this as batteries don't like big currents and so the battery capacity drops a bit, but in your case because you have a big bank, the load is shared by all the batteries, so the current per battery is small enough to ignore this. Not sure if this helps or if I have badly explained it. Let me know and I can improve for the future.
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Post by Gone on Oct 28, 2016 13:28:40 GMT
I was a bit slow typing the above so repeated what was said before, tried to edit it and became confused and had finger trouble, so left it as is. Sorry about that
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Post by tonyb on Oct 28, 2016 14:38:42 GMT
Really the fact that others have given answers is of little consequence because first of all the more answers that say the same the easier it is for the less experienced to judge who is probably giving good info and secondly any of the three answers so fear might contain that little bit of info the allows Bettina to suddenly see what Ah are and how they are used. I think all you need to do is add another post saying - beaten to it or some such.
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Post by Deleted on Oct 28, 2016 14:47:45 GMT
Forgive me, but I have an embarrassingly stupid question about charging batteries.
I have 2x110 batteries for the fridge. The positives are linked, as are the negatives.
Is it better to connect the charger to one battery
or the positive of one and the negative of another?
Rog
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Post by tonyb on Oct 28, 2016 14:50:53 GMT
For the purists the pos. of one and the neg. of the other. Practically do which is easiest.
The more batteries there are in the bank the more important it becomes, it will be the same with the leads supplying the fridge.
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Post by tonyqj on Oct 28, 2016 14:57:26 GMT
For the purists the pos. of one and the neg. of the other. Being pure, and seeing as either is as easy as the other, I would advocate the above.
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Post by Deleted on Oct 28, 2016 15:08:29 GMT
Thank you.
I will resist the temptation to ask why it's better as I have little doubt I'll not understand.
When I'm out for blacking is the only time I use the charger, and so have never confirmed one way or another.
Thanks again.
Rog
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Post by tonyqj on Oct 28, 2016 15:22:16 GMT
Thank you. I will resist the temptation to ask why it's better as I have little doubt I'll not understand. When I'm out for blacking is the only time I use the charger, and so have never confirmed one way or another. Thanks again. Rog It 'balances' the charge between the batteries optimally. Whether it actually makes any difference in practice is arguable.
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Post by tonyb on Oct 28, 2016 15:22:56 GMT
Thank you. I will resist the temptation to ask why it's better as I have little doubt I'll not understand. When I'm out for blacking is the only time I use the charger, and so have never confirmed one way or another. Thanks again. Rog As you did not ask I will tell you. The inter;ink cables joining the two batteries have some resistance so if the cables are both on one end the furthest battery will be getting slightly less charge and delivering slightly less electricity. This means that one battery will always be better charged than the other. By putting the leads on opposite ends the electricity has to flow through the same number of interlinks so both batteries get the same charge and discharge. My own view is that with two batteries it will not make a significant difference but once you get more than two it becomes vital if you want to maximise battery life. Once you get much above four batteries even more complex wiring is needed to ensure each battery is charged and discharged to the same degree.
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Post by smileypete on Oct 28, 2016 15:23:02 GMT
Charge Efficiency/Peukert/Black Magic is all the same thing as far as this guide's concerned. Yeah but Peukert is all but irrelevant for the typical narrowboat owner. There was fundamental misunderstanding of it on CWDF in hindsight, which seemed to be reflected in what you wrote, Nick can fill you in on the details.
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