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Post by tonyqj on Nov 1, 2016 10:50:26 GMT
... regarding this OP my only comment was that float charge isn't really a charging state, it's a maintenance state. The OP text implies that float is necessary to bring a battery to a fully charged state, I'd say this is misleading and counter-productive, especially as we often advocate those charging from a genny not to have a float stage at all. And I disagree. Firstly, the OP doesn't imply that Float is necessary, in fact the OP goes to some lengths to explain why Float is undesirable for most boaters. Secondly, and more fundamentally, you state that 13.6V won't fully charge a 12V lead acid battery. You are wrong. It will. 13.6V will take a long time to finish the charge and it won't get rid of any sulphation but it will finally get the battery approaching 100%. Do we want it to? No, and that is fundamentally what the OP is all about - avoiding Float. Tony
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Post by tonyqj on Nov 1, 2016 10:56:06 GMT
Yes it was. It's a pity folk don't think it was nice for me to try to correct a few minor mistakes. I guess that if you are the OP you can say what you like and not expect to have it corrected. Or was that CWDF? FWIW I appreciate your inputs to these type of threads and don't think that the OP should expect not to have errors corrected. I do sometimes think you can get bogged down in trying to get everything technically correct (according to you) rather than focusing on what the OP was trying to achieve. This is a minor criticism and I could criticise other contributors as well so please don't take offense. Currently I only post on these threads to try to help the discussion move on rather than one of 'ignorance, mischief or boredom', I want to get a better understanding of the basics so that when I come to start making specific questions I can make them fairly specific/detailed rather than 'why have my batteries died again'. My areas of expertise can be summed up as; - Human Factors expert in control center design and operation - Independent technical expert during Union/Management negotiations - Writer of technical/operational/emergency manuals I hope you and others will accept my inputs as potentially helpful (even if they come from someone who is currently fairly ignorant of the technical details). I think the input from someone who is used to writing manuals would be most welcome π I recall a pair of Technics headphones which came with the warning "Excessive turning of the volume control can be damaging to the earholes". It made me laugh, but it got the message across.
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Post by smileypete on Nov 1, 2016 11:17:58 GMT
Secondly, and more fundamentally, you state that 13.6V won't fully charge a 12V lead acid battery. You are wrong. It will. Tony It won't according to the manufacturers definition of a full charge, or that of The Battery FAQ. Secondly, and more 13.6V will take a long time to finish the charge and it won't get rid of any sulphation but it will finally get the battery approaching 100%. Tony There's the rub, 'approaching 100%' is not a full charge if it leaves more sulphate on the plates. I try to get round this by stating 'a proper full charge' as that meeting the manufacturers requirements.
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Post by Telemachus on Nov 1, 2016 11:18:47 GMT
... regarding this OP my only comment was that float charge isn't really a charging state, it's a maintenance state. The OP text implies that float is necessary to bring a battery to a fully charged state, I'd say this is misleading and counter-productive, especially as we often advocate those charging from a genny not to have a float stage at all. Secondly, and more fundamentally, you state that 13.6V won't fully charge a 12V lead acid battery. You are wrong. It will. 13.6V will take a long time to finish the charge and it won't get rid of any sulphation but it will finally get the battery approaching 100%. Tony No hopefully I have never said that 13.6v won't fully charge a LA battery. It will, eventually. What I said was that a more normal float voltage of 13.25v won't. Although of course different batteries have different recommended float voltages, it is interesting that Mastervolt and Victron use 13.25v as the default float voltage (although confusingly, Victron refer to it as "storage" mode) whilst for Sterling it seems to be 13.6v.
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Post by tonyqj on Nov 1, 2016 11:29:14 GMT
Secondly, and more fundamentally, you state that 13.6V won't fully charge a 12V lead acid battery. You are wrong. It will. Tony It won't according to the manufacturers definition of a full charge, or that of The Battery FAQ. Secondly, and more 13.6V will take a long time to finish the charge and it won't get rid of any sulphation but it will finally get the battery approaching 100%. Tony There's the rub, 'approaching 100%' is not a full charge if it leaves more sulphate on the plates. I try to get round this by stating 'a proper full charge' as that meeting the manufacturers requirements. What's a full charge? 100% is unobtainable, all one can ever achieve is 'approaching full charge' as stated in the OP.
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Post by tonyqj on Nov 1, 2016 11:32:54 GMT
Secondly, and more fundamentally, you state that 13.6V won't fully charge a 12V lead acid battery. You are wrong. It will. Tony It won't according to the manufacturers definition of a full charge, or that of The Battery FAQ. Secondly, and more 13.6V will take a long time to finish the charge and it won't get rid of any sulphation but it will finally get the battery approaching 100%. Tony There's the rub, 'approaching 100%' is not a full charge if it leaves more sulphate on the plates. I try to get round this by stating 'a proper full charge' as that meeting the manufacturers requirements. On reflection, I'm not sure that I understand what point you are making with reference to the OP. I'll happily edit it if I can be shown an error.
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Post by Deleted on Nov 1, 2016 11:35:38 GMT
I think the input from someone who is used to writing manuals would be most welcome π Thank you. In my Manual writing days I often used an 'Info Box' to deflect the techies, normally contained words to the effect that this statement is disputed - I'd leave the techies to come up with the exact wording. Meanwhile the techies could not understand why the rest of us were on our third round in the pub before they arrived!
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Post by Telemachus on Nov 1, 2016 11:35:43 GMT
I think it boils down to whether you think that "fully charged" means all the lead sulphate converted to lead and acid, or just that which is easy to convert! If the absorption voltage is held to "fully charged", then go to float, I think that is preferable to going to float before quite fully charged. In fact the latter seems to be a common source of problems.
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Post by Telemachus on Nov 1, 2016 11:38:08 GMT
I think the input from someone who is used to writing manuals would be most welcome π Thank you. In my Manual writing days I often used an 'Info Box' to deflect the techies, normally contained words to the effect that this statement is disputed - I'd leave the techies to come up with the exact wording. Meanwhile the techies could not understand why the rest of us were on our third round in the pub before they arrived! But you have to bear in mind that a lot of the stuff on these two threads is us arguing over the finer points. It is not aimed at the beginner! But in order to come up with the best beginners text, it's necessary (IMO) to know the full picture, before applying the simplifications.
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Post by tonyqj on Nov 1, 2016 11:43:44 GMT
I think it boils down to whether you think that "fully charged" means all the lead sulphate converted to lead and acid, or just that which is easy to convert! If the absorption voltage is held to "fully charged", then go to float, I think that is preferable to going to float before quite fully charged. In fact the latter seems to be a common source of problems. I agree. To convert all of the lead sulphate can take hours and hours at quite a high voltage. By the time you've succeeded you've also increased plate corrosion.
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Post by Graham on Nov 1, 2016 11:44:32 GMT
Secondly, and more fundamentally, you state that 13.6V won't fully charge a 12V lead acid battery. You are wrong. It will. 13.6V will take a long time to finish the charge and it won't get rid of any sulphation but it will finally get the battery approaching 100%. Tony No hopefully I have never said that 13.6v won't fully charge a LA battery. It will, eventually. What I said was that a more normal float voltage of 13.25v won't. Although of course different batteries have different recommended float voltages, it is interesting that Mastervolt and Victron use 13.25v as the default float voltage (although confusingly, Victron refer to it as "storage" mode) whilst for Sterling it seems to be 13.6v. Storage mode because that is what it is designed to be. A mode that will hold a battery in its best condition and reduce or stop itself discharge; so that it can sit there for weeks and months with minimum damage or loss of charge. That is all float mode is designed to do nothing else.
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Post by tonyqj on Nov 1, 2016 11:45:43 GMT
I wonder if it's worth adding a caveat under the 'Float charge' section pointing out that some chargers set Float at an undesirably low voltage?
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Post by Graham on Nov 1, 2016 11:49:30 GMT
Thank you. In my Manual writing days I often used an 'Info Box' to deflect the techies, normally contained words to the effect that this statement is disputed - I'd leave the techies to come up with the exact wording. Meanwhile the techies could not understand why the rest of us were on our third round in the pub before they arrived! But you have to bear in mind that a lot of the stuff on these two threads is us arguing over the finer points. It is not aimed at the beginner! But in order to come up with the best beginners text, it's necessary (IMO) to know the full picture, before applying the simplifications. But we do not need to be discussing the finer points. It is very simple does the article about whatever put across in a reasonable way what the author is attempting to put across. If the answer is yes end of story if no in simple terms what should it say. No complicated newton's law etc just to get the layman to understand we need to say xxxx
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Post by Telemachus on Nov 1, 2016 11:49:59 GMT
I wonder if it's worth adding a caveat under the 'Float charge' section pointing out that some chargers set Float at an undesirably low voltage? No it isn't an undesirably low voltage. Gibbo told me that 13.25v was a good voltage for long term float since it kept plate corrosion to a minimum whilst keeping the battery just about full. It's back to my original point that float is a storage or maintenance mode, it isn't supposed to be a charging mode. The important point is to ensure that the battery is "fully charged" before going to float.
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Post by Graham on Nov 1, 2016 11:51:09 GMT
I wonder if it's worth adding a caveat under the 'Float charge' section pointing out that some chargers set Float at an undesirably low voltage? No I do not think so, but I would also suggest that that section should not lump it in as part of the natural charging cycle.
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