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OK, I am ready to tootle about in my NB, starting in May, June.

I epect I will moor up Dec to March, with, or even without shore power, happy to stay in a marina for a few days or weeks per month Nov - March.. I  might take a mooring, I might keep movng.

I am OK to run engine for an hour every day to keep batteries happy if they need a pep.

I currently have 3x135 new AGMs and two older, but decent AGMs at the bow.

Since newbatteries arrived, everything "works"

C

Edited by LadyG
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With adequate solar you should not need to run the engine in summer, provided we get one.  If you do need extra, running the engine for an hour a day is probably the fastest way to ruin your batteries after not charging them at all.  An hour of engine  a day, without other charging, leaves your battery part discharged and sulphating merrily.  Aim to run the engine or a generator and battery charger so that the battery is fully charged as often as possible and at least once a week.  Fully charging takes a long time-allow for about a 6 to 8 hour run if doing it weekly and probably 4 to 5 hours if doing it daily.

 

Adequate solar, or what you need from the engine or generator can only be defined after you do a power audit.  I think there is an audit calculator on Tony Brooks website.

 

N

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As said you need to do a power audit to be sure, but for most people 500 to 600 watts seems about right for the odd day with no engine, if only using the engine once a fortnight for a hour or so then nearer 1000 watts would be better, allowing for partial shade and dull 'orrible days. This is for cruising March to September with NO electric heating at all.

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4 hours ago, LadyG said:

Since newbatteries arrived, everything "works"

 

Until you wreck them by undercharging, which seems imminent from the way you constructed your question.

 

LA batteries need FULLY charging twice a week and a 'pep' (as you call it) once a day. 

 

Or do it the mrsmelly way and buy new batts every time you wreck them ;)

 

 

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1 hour ago, Mike the Boilerman said:

Or do it the mrsmelly way and buy new batts every time you wreck them ;)

 

 

Its a tempting route to take. My latest set of batteries I have looked after the best way I can. Pure Lead Carbon, monitored with BMV and Smartguage, charged regularly with extensive cruising, small amount of solar until I had more added this winter, and engine running when sitting in a spot for any length of time where solar wasn't sufficient to recharge. After all that my current readings still show I've lost about 1/3 of their capacity since a year and a half ago. Not sure where the problem lies, or if these batteries are particularly affected by cooler temperatures capacity-wise, but I've tried to stop thinking about it too much and will just use them until they're unusable. 

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Yes, sorry, I meant I will run engine for an hour to get the alternator to start the charging regime for the day, if there is any doubt that they won't have a good charge via the solar that day. This replicates my present strategy which has the mains charger on for about an hour to top batteries up in the morning, and again while the Webasto is/has been running. I monitor the SOC by the voltage on the voltmeters, and the traffic lights on the mains charger.  The lowest voltage indicated is 12.4, more usually 13.4, and 16v when I put the charger on.  I use very little 12v at the moment as I am on shorepower for the fridge and the laptop. So I know how many units I actually use on top of water pump, and showers. 

The mains fridge is to be replaced with one that is rated at 65 watts, using a solar calculator I will use 1.7 Kwh per day, which is in line with my shorepower usage all year round.

My lead acid battery [domestic] bank of 450 ah and 550 watt solar should provide autonomy for three cloudy days, but I would avoid getting down to 50% , might even travel on these days!

The Webasto is the biggest drain on power, kicking in at a time when there is no sunlight, my present solar , [240 w] just does not compensate, which is why I bought two 275W panels.

NOW HERE IS THE PROBLEM

My electrician is a bit of a genius, but we disagree on the solar requirement. He reckons I should sell my new 550W kit, stick with the old 240W regime which is cobbled togther with insulating tape instead of waterproof connectors, I am not sure if there is an isolator, it was installed by original owner. It works.

My electricians have both avoided connecting in to any of "original system", much of the spagetti wiring has been removed. I have a new 375W Victron Invertor fitted in the bow.

The original plan was to add the new solar kit, fitting cost is now a stumbling block, its not far off £700 if I include £100 for mounting clamps, screws etc.

Can I just rip out original solar electrics and put the new panels on top of the old, and hope they stay in place , they can be screwed/clamped on to the old panels. and tied down with Dyneema in stormy weather. All this is at the stern, but the invertor is at the bow with the sockets.

The fitter's argument is that there is plenty of power from the solar on a good day. He does not want to drill holes in roof, and clutter the roof [I have two bikes as well], [fitting will cost me £700 [two days work which includes three hours travel per day]. I think replacing existing solar, while losing 240W[3x80], will give a net gain of 310W, ie two new panels, no extra brackets, no extra holes in roof. 

PS I hope to cc three seasons or get a cheap mooring locally,  and stay in a marina with power in the dead of winter. 

 

 

Edited by LadyG
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5 hours ago, LadyG said:

This replicates my present strategy which has the mains charger on for about an hour to top batteries up in the morning, and again while the Webasto is/has been running. I monitor the SOC by the voltage on the voltmeters, and the traffic lights on the mains charger.  The lowest voltage indicated is 12.4, more usually 13.4, and 16v when I put the charger on.

1) Why not just leave the mains charger on 24/7 ?

 

2) If you are charging at 16 volts for more than 'a few minutes' you'll be killing your batteries. This voltage should only be used infrequently for a short period for equalisation.

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1 hour ago, Alan de Enfield said:

1) Why not just leave the mains charger on 24/7 ?

 

2) If you are charging at 16 volts for more than 'a few minutes' you'll be killing your batteries. This voltage should only be used infrequently for a short period for equalisation.

The charger is part of original electrickery, definately not smart.

 I think I do have two chargers, one is a tiny [?5 amp] modern LED with  LED [?input] voltmeter I think it is on 24/7 but not pumping 5 amps in when batteries fully charged;

The 20 amp one may be a canibalised thing which has five traffic lights, no voltage indicator, there is a small voltmeter [the round dial type] nearby which has a red line at 16v. I assumed I would be OK if I did it manually I turn it ON if in amber zone and OFF in the green zone, I equate two greens as equalisation. One green as float, amber as absorption.

When I had flooded lead acid, they enjoyed a good bubbling once or twice when I left this charger ON. 

All batteries are now AGM, engine starts easily even if left for months.?

To re-wire the boat would have cost about £5K, so opted for the slowly slowly approach.

Put a new 12v supply line [for a new fridge], which is now double fused at battery end. Old 12v fridge was supplied from shorepower via transformer/power bank. Not sure if the transformer will be sold with the fridge.

 

Edited by LadyG
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10 hours ago, Rumsky said:

Its a tempting route to take. My latest set of batteries I have looked after the best way I can. Pure Lead Carbon, monitored with BMV and Smartguage, charged regularly with extensive cruising, small amount of solar until I had more added this winter, and engine running when sitting in a spot for any length of time where solar wasn't sufficient to recharge. After all that my current readings still show I've lost about 1/3 of their capacity since a year and a half ago. Not sure where the problem lies, or if these batteries are particularly affected by cooler temperatures capacity-wise, but I've tried to stop thinking about it too much and will just use them until they're unusable. 

 

This is interesting and must be very disappointing for you. I thought the whole point of lead carbon batts is that they are claimed by the manus not to sulphate up, but you appear to have illustrated otherwise. Assuming the loss of capacity IS sulphation. In fact IIRC the manus also claim you don't have to keep them fully charged anyway.

 

Have you been bothered enough to ask the manu about it?

 

Does a Smartgauge actually work correctly with lead carbon batts? I've not noticed any mention of them in the SG manual.

 

 

 

 

 

 

 

Edited by Mike the Boilerman
Pressed "Submit Reply" too soon!
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you can get digital volt meters on ebay for about £1-50 a time, they may not be as good as a fluke meter for accuracy but they will tell the difference between 14 and 16 volts. Doesn't the smart meter have a voltage reading as well as percentage? not ever having one I don't know

Do you have a hand held meter where you could check the voltage while charging on the battery terminals

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43 minutes ago, Mike the Boilerman said:

 

This is interesting and must be very disappointing for you. I thought the whole point of lead carbon batts is that they are claimed by the manus not to sulphate up, but you appear to have illustrated otherwise. Assuming the loss of capacity IS sulphation. In fact IIRC the manus also claim you don't have to keep them fully charged anyway.

 

Have you been bothered enough to ask the manu about it?

 

Does a Smartgauge actually work correctly with lead carbon batts? I've not noticed any mention of them in the SG manual.

 

 

 

 

 

 

 

The blurb from Leoch states they significantly reduce sulphation but didn't give any specifics. They also state faster charging than regular lead acid but can't say I've noticed any difference. 

 

I haven't contacted the manufacturer yet but I may do in future to see what they say. 

 

I called up the wizard about the Smartguage when I installed them to ask which setting would be appropriate for these and they said to use option 5 'Carbon Fibre Lead Acid'. Looking at the resting voltage it seems to about right for SoC most of the time.

 

I can only conclude from BMV readings capacity has somehow been reduced, all my charging seems to work OK. Solar and alternator at 14.6 - 14.8v, mains smart charger only goes to 14.2 and shuts off way too early but rarely use that. 

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21 minutes ago, Rumsky said:

I haven't contacted the manufacturer yet but I may do in future to see what they say. 

 

Do let us know what they say, if you get around to it. They are sure to have a well rehearsed rebuttal to prove it is All Your Fault, but it will be interesting to find out how they square it with their marketing claims and puff. 

 

Sounds to me as though you might be better off cutting your losses and getting some lithiums, given you have a good grip on things and use the boat a lot.

 

 

Edited by Mike the Boilerman
Fiddle with it
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1 hour ago, jddevel said:

What are the views of those who advocate electric propulsion regarding battery maintenance especially if no landline mains connection available? 

Traction batteries. While you inevitably abuse batteries if you cannot apply the recommended daily charge regime, tractions are designed for the job and in my experience will survive the abuse for far longer (14 years so far in my case). As much solar as you can fit , but especially on a narrow boat, this will only help to reduce the hours which, in the absence of shore power, a good generator must run. Needs to be able to charge at C5, or 20 percent of bank capacity, so likely a built in of over 5kw.

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8 minutes ago, Mike the Boilerman said:

 

Do let us know what they say, if you get around to it. They are sure to have a well rehearsed rebuttal to prove it is All Your Fault, but it will be interesting to find out how they square it with their marketing claims and puff. 

 

 

 

That was sort of my thinking as well which I suppose is why I haven't got round to doing it yet. 

 

I considered lithiums before I bought these. Although expensive, I enquired about the drop-in direct replacements for lead acid with all the gubbins onboard the battery. I explained to them what I had and the retailer advised me I would have to replace all of my charging system as well, which I though kinda defeated the whole 'drop-in' aspect. 

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7 minutes ago, Rumsky said:

That was sort of my thinking as well which I suppose is why I haven't got round to doing it yet. 

 

I considered lithiums before I bought these. Although expensive, I enquired about the drop-in direct replacements for lead acid with all the gubbins onboard the battery. I explained to them what I had and the retailer advised me I would have to replace all of my charging system as well, which I though kinda defeated the whole 'drop-in' aspect. 

 

Yes there is no such thing as a "drop-in" replacement, yet.  The Big Problem is they must not be overcharged or they will be wrecked so disconnection of the alternator as they approach fully charged is mandatory. This wrecks alternators instead. No-one has developed a "drop-in" fix for this conundrum yet. 

 

The nearest fix is to keep a LA battery in parallel to absorb the alternator charge. Reasonably simple, but means some external wiring is needed so not a pure "drop-in" solution. 

 

 

Edited by Mike the Boilerman
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5 minutes ago, Mike the Boilerman said:

 

Yes there is no such thing as a "drop-in" replacement, yet.  The Big Problem is they must not be overcharged or they will be wrecked so disconnection of the alternator as they approach fully charged is mandatory. This wrecks alternators instead. No-one has developed a "drop-in" fix for this conundrum yet. 

 

 

I'll see how these go and if they deteriorate further I will contact the manufacturer. Once these are knackered I'll probably just go back to cheapo lead acid until the lithium problem is solved or becomes simpler and more affordable. 

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1 minute ago, Rumsky said:

I'll see how these go and if they deteriorate further I will contact the manufacturer. Once these are knackered I'll probably just go back to cheapo lead acid until the lithium problem is solved or becomes simpler and more affordable. 

 

Yes a good policy probably. 

 

One needs to live and breathe lithium for a few months initially, if you install them. Once you have their measure, they are a breeze to live with. But you NEED to understand them.

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20 minutes ago, Mike the Boilerman said:

 

Yes a good policy probably. 

 

One needs to live and breathe lithium for a few months initially, if you install them. Once you have their measure, they are a breeze to live with. But you NEED to understand them.

I don't really fancy adding breathing in lithium to the coronavirus, coal and wet wood fumes, and that 'orrible red diesel stuff, so I'll wait until they've all been banned before I switch. 

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58 minutes ago, Rumsky said:

That was sort of my thinking as well which I suppose is why I haven't got round to doing it yet. 

 

I considered lithiums before I bought these. Although expensive, I enquired about the drop-in direct replacements for lead acid with all the gubbins onboard the battery. I explained to them what I had and the retailer advised me I would have to replace all of my charging system as well, which I though kinda defeated the whole 'drop-in' aspect. 

There is the story of a Lithium upgrade here, https://derwent6.blogspot.com/2019/04/day-three-of-our-upgrade.html it all seems to be working fine now but not straightforward 

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2 hours ago, Alan de Enfield said:

Amended.

 

I think there is probably only one on the forum who could answer that.

Um, no.

 

Like I said, I've been living on a self designed electric propelled NB for 14 years now. Since it was/is all experimental and still WIP I've not been preaching too much about it, but it all works, and because it's a really robust power system, is a superbly efficient live aboard set up.

Like those above, I'm not yet convinced of the practicality of switching to lithium.

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3 hours ago, ditchcrawler said:

you can get digital volt meters on ebay for about £1-50 a time, they may not be as good as a fluke meter for accuracy but they will tell the difference between 14 and 16 volts. Doesn't the smart meter have a voltage reading as well as percentage? not ever having one I don't know

Do you have a hand held meter where you could check the voltage while charging on the battery terminals

Is this for me?

I have no desire to buy things at £1.50 off  Ebay, there is enuff electrickery of that sort already.

We are simplifying the system, one day at a time.

I don't need a multimeter or another voltmeter, or a cheap multimeter, I want a system that has decent batteries, and I  will manage input and output in summer it should look after itself.

 

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