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Post by Deleted on Feb 21, 2019 20:09:29 GMT
15 months sounds reasonable. I'm another keep it simple type with just one battery on my cruising boats. only thing is its also the start battery...
That helps concentrate the mind on power usage of an evening.
Diy lipo jump starter standing by in case of miscalculations.
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Post by Deleted on Feb 21, 2019 20:31:54 GMT
15 months sounds reasonable. I'm another keep it simple type with just one battery on my cruising boats. only thing is its also the start battery... That helps concentrate the mind on power usage of an evening. Diy lipo jump starter standing by in case of miscalculations. Yep, another 18 months with a lead acid battery. then hopefully technology will give me a pocket size lithium battery which will do the trick.,
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Post by peterboat on Feb 21, 2019 20:50:48 GMT
15 months sounds reasonable. I'm another keep it simple type with just one battery on my cruising boats. only thing is its also the start battery... That helps concentrate the mind on power usage of an evening. Diy lipo jump starter standing by in case of miscalculations. Yep, another 18 months with a lead acid battery. then hopefully technology will give me a pocket size lithium battery which will do the trick., i have 14 of them already fantastic beasties to say the least
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Post by Deleted on Feb 21, 2019 20:57:01 GMT
Yep, another 18 months with a lead acid battery. then hopefully technology will give me a pocket size lithium battery which will do the trick., i have 14 of them already fantastic beasties to say the least Show off.
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Post by Deleted on Feb 23, 2019 0:28:03 GMT
Well I’ve bought another 030 70ah battery
Not fitted it yet but thought I’d give it a trickle charge at the missus’s house first. Much to my surprise, although it measured 12.6v, it has been sucking in amps for many hours.
A while back I read an article about the fact that we don’t always know how long ‘new’ batteries have been lying around. So true!
It will be interesting to see if the new battery cures the low charging voltage issue. I’ve got a new battery isolator on order just in case.
I still haven’t ruled out the alternator yet either. Will feedback findings in due course..
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Post by Deleted on Feb 23, 2019 13:41:57 GMT
Just replaced suspect battery with new fully charged battery (£70). Started engine and waited 5 mins or so for the engine starter battery to replace the cranking current. Charging voltage settled at around the normal 14.4v. So although I don’t want to tempt fate, it does look like the reduced charging voltage I saw before was a symptom of the failing battery. I’m not sure what happens inside lead acid batteries when they start going U/S but it does look like it is some kind of short. Probably enough to see about 1.5v drop still after 2 hours charging, yet only enough the see a few amps being lost due to the short. I’m glad now that I fitted an LED voltmeter in the cabin area as I can see instantly if something is staring to go wrong with the charging circuit and I can keep a constant check on the charge state of the battery. The only problem is that I think I’ve become a little too OCD with it.
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Post by Jim on Feb 23, 2019 14:20:35 GMT
Just replaced suspect battery with new fully charged battery (£70). Started engine and waited 5 mins or so for the engine starter battery to replace the cranking current. Charging voltage settled at around the normal 14.4v. So although I don’t want to tempt fate, it does look like the reduced charging voltage I saw before was a symptom of the failing battery. I’m not sure what happens inside lead acid batteries when they start going U/S but it does look like it is some kind of short. Probably enough to see about 1.5v drop still after 2 hours charging, yet only enough the see a few amps being lost due to the short. I’m glad now that I fitted an LED voltmeter in the cabin area as I can see instantly if something is staring to go wrong with the charging circuit and I can keep a constant check on the charge state of the battery. The only problem is that I think I’ve become a little too OCD with it. I have a digital V/Ah meter near the batteries, also one 30ft away that came as part of a lighter socket/USB plate, it measures a couple of tenths down on the other, voltage drop on cable run. So depending on your run and cable you may have more power than you think.
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Post by Deleted on Feb 23, 2019 14:23:53 GMT
Just replaced suspect battery with new fully charged battery (£70). Started engine and waited 5 mins or so for the engine starter battery to replace the cranking current. Charging voltage settled at around the normal 14.4v. So although I don’t want to tempt fate, it does look like the reduced charging voltage I saw before was a symptom of the failing battery. I’m not sure what happens inside lead acid batteries when they start going U/S but it does look like it is some kind of short. Probably enough to see about 1.5v drop still after 2 hours charging, yet only enough the see a few amps being lost due to the short. I’m glad now that I fitted an LED voltmeter in the cabin area as I can see instantly if something is staring to go wrong with the charging circuit and I can keep a constant check on the charge state of the battery. The only problem is that I think I’ve become a little too OCD with it. I have a digital V/Ah meter near the batteries, also one 30ft away that came as part of a lighter socket/USB plate, it measures a couple of tenths down on the other, voltage drop on cable run. So depending on your run and cable you may have more power than you think. Yes I agree that the voltmeter should ideally be as close to the battery as possible. However I use it just to get some idea of what’s going on. I can’t spend ALL my life in the engine room.
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Post by Jim on Feb 23, 2019 14:25:10 GMT
I have a digital V/Ah meter near the batteries, also one 30ft away that came as part of a lighter socket/USB plate, it measures a couple of tenths down on the other, voltage drop on cable run. So depending on your run and cable you may have more power than you think. Yes I agree that the voltmeter should ideally be as close to the battery as possible. However I use it just to get some idea of what’s going on. I can’t spend ALL my life in the engine room. I agree, I just compensate for the reading on the one at the bow.
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Post by Telemachus on Feb 23, 2019 16:40:09 GMT
I think the relevant test will be once the domestic battery has been depleted a bit and you want to recharge it.
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Post by Deleted on Feb 23, 2019 17:42:43 GMT
I think the relevant test will be once the domestic battery has been depleted a bit and you want to recharge it. Agreed, I'd have fitted it as is and gave the alternator something to think about.
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Post by ianali on Feb 23, 2019 19:01:53 GMT
Not wishing to derail this thread, but will ask anyway. Our boat has a simple battery set up. 4 x110 amp leisure batteries. Charged by 110 amp charger. Batteries into their fifth year, still doing ok. I only read the battery voltage from the inverter read out. Just to clarify, I have no problems with the batteries, touch wood! My question is this. When Ali uses her hairdryer it is with the engine running. The voltage shown when the dryer is on is usually around 13.3 volts. Does this mean that the hair dryer is only using the alternator power? Or is it also draining the batteries?
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Post by Deleted on Feb 23, 2019 19:16:16 GMT
Given that fully charged lead acid 12v batteries are about 12.7v it seems that the load drawn by the hairdrier is indeed being supplied by the alternator.
It depends when you measure the voltage and how long the hairdrier is being operated for.
If the batteries always stay above the nominal 12.7v then they are effectively being charged rather than discharged.
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Post by ianali on Feb 23, 2019 19:23:06 GMT
Given that fully charged lead acid 12v batteries are about 12.7v it seems that the load drawn by the hairdrier is indeed being supplied by the alternator. It depends when you measure the voltage and how long the hairdrier is being operated for. If the batteries always stay above the nominal 12.7v then they are effectively being charged rather than discharged. Yeh this is what I thought but I know little about such things. I’m moored at top of the Ashby, it’s quiet and I probably have to much time on my hands.
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Post by Deleted on Feb 23, 2019 19:26:59 GMT
Ashby is pleasant but I would suggest a bit of boating to get to somewhere with locks. Locks are always good specially in this ridiculously nice weather. Assuming its nice up there. Has been amazing down in Londonland we even managed a trip to Sarfend on sea on the train today. Glorious sunshine (to quote dogless) and tomorrow more Glorious sunshine predicted so I will be having a little cruise down the Thames through 10 of its locks.
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