Inverter is on the fritz, maybe

[wandering]

4 hours ago, LadyG said:

I'm surprised no one has suggested the installation of solar panels. To me this is essential for off grid boater unless they are going to cruise two, three, four hours (I'm not sure how long) every day.

I too bought a boat previously connected to shore power. There were far too many batteries on my boat, the huge capacity meant I would never be able to top up the batteries every day, so I replaced ( domestic bank), them with smaller capacity but same configuration. The guy who did this was able to identify which batteries were dying a slow death. He was pretty good,  and I still have his batteries four years later. All the batteries in one bank need to be replaced at one time.

I have two solar panels on the roof which top up the batteries for seven months of the year. In winter I am frugal with my electricity usage (I only have fridge on when engine is running, so I'm using it as a larder). It is always Off overnight, so no frozen food.

Regular trips to the launderette and a solid fuel stove with back boiler see me through the winter. I run the engine to top up batteries and it  also  heats my water. 

Most domestic batteries used by boaters are Flooded Lead Acid which need regular maintenance, not difficult if they are accessible. The capacity of the solar panels is critical, I replaced the original 100W panel with two 275W panels and a matched controller.

 

 

Solar is on my to do list. I am just uncertain how much I might need… time for the energy audit

11 hours ago, Loddon said:

I have used these

https://batterystore.co.uk/leoch-sfl-130dt-leisure-battery/

Lasted 4 years

Then changed for these

https://batterystore.co.uk/leoch-lagm-130-leisure-battery/

Last October

 

Battery Store is in Market Harborough so not far from you and will do discounts if you collect 3 or 4 batteries

Have you noticed much / any difference between the two?

[MtB]

11 hours ago, wandering said:

I wish learning curves were cheaper 😆

 

Ah now there is a BIG risk here you need to be aware of, I see you about to fall foul of.

 

General opinion in the thread is you need a new set of batteries. I was in the same position once, in that I bought a new set of batteries long ago for much the same reasons as you look about to. Great, everything worked again! 

 

But I pretty rapidly knackered them from not really understanding just how important it is to charge them properly, and in particular not properly understanding what 'charge them properly' really means. So I learned properly by reading and studying dozens of old threads on here, then buying the right monitoring kit and ANOTHER set of new batteries. I promptly knackered this new set too, as my understanding was not complete, coupled with my new monitoring device turning out to be wrongly calibrated out of the box. 

 

So my point is, I think it takes ruining two new sets of domestic battery banks at £500 a pop before one really gets to understand how to maintain lead acid batteries well. For that money you can buy some lithium batteries instead, which work brilliantly but present you with a totally different set of problems - mostly involving new alternators . 

 

 

 

 

 

Edited March 27, 2023 by MtB
Add a bit.

[Tony Brooks]

2 minutes ago, wandering said:

Solar is on my to do list. I am just uncertain how much I might need… time for the energy audit

 

If you intend to cruise during the colder months then as much as will fit or you can afford. Even then you will still have to do other charging during the winter. Otherwise, you are likely to ruin the new set of batteries. Lithium batteries will need a bit less solar but the care and monitoring of such batteries is more exacting to ensure you do not damage them by over charging or over discharging than with lead acids.

 

The result of the power audit can be very misleading with lead acids until you grasp just how much and how fast the charging current will drop from any source. For instance, you can only rely upon an alternator to deliver about half its rated output on average over three to four hours and less and less on average as the time is extended. You will see this on your battery monitor amps readout if you check it regularly while cruising. Solar is even worse because the day length and brightness is constantly altering. 

 

My view is that you will do best by learning how to monitor your batteries so in summer you know when you need to use the alternator. By and large engine charging early in the day for two hours or so and then allow the solar to do the very long slow charge that is needed to get the bank fully charged is probably the most efficient way. The length of the engine run will depend on the size of the solar.

 

 

[Tracy D'arth]

Batteries around 10 years old are beyond hope. Learn how to take care of the new set BEFORE installing them.

Leaving batteries on charge in a marina off the mains supply will not take care of them indefinitely, no battery charger is perfect, no battery lasts for ever.

Yours are toast my friend.

[LadyG]

The Galvanic Isolator is only required when attached to shoreline electricity, it is to prevent hull corrosion. 

Maybe phone the marina and ask for recommendation for an electrician who can check your batteries and fit the solar. These things can be done by a experienced boater, with good tools, but not so easy for the average person. Think of the money you are saving as you sign the cheque! 

It's a good idea to build up your knowledge of boat electrics and batteries, plus solar before you decide what to do.

I used a solar kit from Bimble Solar, this ensures you get the panels, cabling, controller, cabling to batteries matched. Obviously take full advantage of advice from the professionals.

Be aware that covering the roof with panels may give you more power,  at an increasing cost, but it means you have to be very careful when manoeuvring the boat with the centreline. 

 

Edited March 27, 2023 by LadyG

[MtB]

5 minutes ago, Tracy D'arth said:

Batteries around 10 years old are beyond hope. Learn how to take care of the new set BEFORE installing them.

 

There is a paradox here. The very BEST and fastest way to learn to take care of a new set of batteries is to buy one, then knacker it immediately.

 

DAMHIK.

[GUMPY]

1 hour ago, wandering said:

Have you noticed much / any difference between the two?

Haven't really used the AGM fully but they seem better.

I would go for the cheaper ones because mist people manage to wreck their first new set of batteries in short order. 😱

It's easily done.

[blackrose]

14 hours ago, David Mack said:

 

Solar will help in summer but is pretty useless in winter.

 

That's not been my experience. Since installing my panels last November I've largely been off grid with fully charged batteries. There have been some occasions where it's been very cloudy and raining for days on end when I've had to switch back to shore power, but in general it's been great and I've been able to run the whole boat from the 4m2 of panels, including a small mains larder fridge, watching TV every evening until late and even running the automatic washing machine when the sun comes out.

13 hours ago, mrsmelly said:

Long life milk is up there with margarine, and so called spreadable butter muck. Retailers worldwide should receive a minimum 3 years custodial sentence for selling the vile garbage!! Skimmed and semi skimmed milk should be a minimum 2 year sentence.

 

I like long life skimmed milk. You're not forced to buy it are you? 😂

[MtB]

4 minutes ago, blackrose said:

 

That's not been my experience. Since installing my panels last November I've largely been off grid with fully charged batteries. There have been some occasions where it's been very cloudy and raining for days on end when I've had to switch back to shore power, but in general it's been great and I've been able to run the whole boat from the 4m2 of panels, including a small mains larder fridge, watching TV every evening until late and even running the automatic washing machine when the sun comes out.

 

That is truly phenomenal performance for 4m2 of panels during winter. What panels exactly did you buy, please?

 

 

Are you tilting them or are they laid flat?

 

 

[blackrose]

12 hours ago, Tony Brooks said:

 

I think David meant that using the blanket has done no long term damage to the batteries as long as you recharge them ASAP. I agree with him, but that does not mean the batteries were not in a bad way before that.

 

Perhaps part of the solution for the OP is to STOP USING THE ELECTIC BLANKET! 🤣

 

And don't run immersion heaters, electric kettles, microwaves ovens, toasters, etc, from your inverter unless it's for a very short time and you are sure you can put that power back into your batteries.

 

[Tony Brooks]

Just now, blackrose said:

 

Perhaps part of the solution for the OP is to STOP USING THE ELECTIC BLANKET! 🤣

 

And don't run immersion heaters, electric kettles, microwaves ovens, toasters, etc, from your inverter unless it's for a very short time and you are sure you can put that power back into your batteries.

 

 

I think he has got that message now BUT I very much fear he finds "electrics" too difficult to get on top of battery monitoring. Even without those heavy drains, given time, he will still ruin his batteries by failing to keep them charged and over discharging them.

[blackrose]

23 minutes ago, MtB said:

 

That is truly phenomenal performance for 4m2 of panels during winter. What panels exactly did you buy, please?

 

 

Are you tilting them or are they laid flat?

 

 

 

Two of these Canadian Solar 455w panels (connected in series and using a Epever 60amp MPPT controller)

 

I use them both flat and sometimes tilted - and it's the tilting that really gives the best results in winter. 

 

Edit: And you were right by the way. I got rid of my silly inefficient gas fridge (actually sold it for £240) and replaced it with a much more efficient mains fridge which runs from the inverter/panels. 

 

Edited March 27, 2023 by blackrose

[Bee]

13 hours ago, mrsmelly said:

Long life milk is up there with margarine, and so called spreadable butter muck. Retailers worldwide should receive a minimum 3 years custodial sentence for selling the vile garbage!! Skimmed and semi skimmed milk should be a minimum 2 year sentence.

Nothing quite like tea made with sterilised milk and a really cheap tea bag from a roadside tea van. I think you're a bit harsh about the semi skimmed and low fat spread, that's part of my healthy eating regime along with avocado on whole grain toast and quinoa.

[mrsmelly]

12 minutes ago, Bee said:

Nothing quite like tea made with sterilised milk and a really cheap tea bag from a roadside tea van. I think you're a bit harsh about the semi skimmed and low fat spread, that's part of my healthy eating regime along with avocado on whole grain toast and quinoa.

When I was a kid my Grannie always bought that sterilised milk, iirc it came in taller bottle with a thinner neck lol.

[Tony Brooks]

1 minute ago, mrsmelly said:

When I was a kid my Grannie always bought that sterilised milk, iirc it came in taller bottle with a thinner neck lol.

 

and a beer bottle style crown cap.

[Higgs]

4 minutes ago, mrsmelly said:

When I was a kid my Grannie always bought that sterilised milk, iirc it came in taller bottle with a thinner neck lol.

 

A school friend used to have it. Didn't like it, but his mother made the best chips I've ever had. Still never beaten.

 

 

[wandering]

1 hour ago, Tony Brooks said:

 

I think he has got that message now BUT I very much fear he finds "electrics" too difficult to get on top of battery monitoring. Even without those heavy drains, given time, he will still ruin his batteries by failing to keep them charged and over discharging them.

something being hard never stopped me from learning. Just takes me more time. I will get on top of this. Already studying your website of electricity treasure, even if it is going over my head right now. 

[MtB]

2 minutes ago, wandering said:

something being hard never stopped me from learning. Just takes me more time. I will get on top of this. Already studying your website of electricity treasure, even if it is going over my head right now. 

 

 

To give yourself some breathing space while you learn about batteries, my suggestion is different from everyone else's here.

 

Before buying a new set of domestics, I think the quickest fix will be to buy a 'drop in' lithium battery (for similar same money) and connect it in parallel with your existing knackered domestic bank. They are near-impossible to destroy due to the integrated battery management system (BMS) and one will give you instant charge capacity.

 

One of these, say: 

https://www.lifebatteries.co.uk/product-page/12v-100ah-self-heating-bluetooth-bms

 

The main risk is to your alternator which might overheat from too much charge current. There is a simple way around this.

 

 

[Tony Brooks]

2 minutes ago, wandering said:

something being hard never stopped me from learning. Just takes me more time. I will get on top of this. Already studying your website of electricity treasure, even if it is going over my head right now. 

 

That is very good to hear, keep at it.  For now, grasp that "rested battery voltage" is the voltage with no electrical loads and with no"surface charge". Surface charge is an artificially higher voltage when you take the batteries off charge. To get rid of it either just use as normal for 15 minutes or so, or leave to stand for at least an hour, overnight is better.

 

Even if there is a small load running like an LED light the results will just imply that you have alower state of charge than t really is.

 

So: 12.7 to 12.8 = more or less fully charged

12.5 = half charged if you want a long battery life.

12.2 to 12.3 = stop discharging and recharge ASAP, again if you want a long battery life.

 

The last two are roughly 3/4 charged and half charged respectively, but by sticking o the figures I give helps maximise the cyclic life of the batteries.

[Alan de Enfield]

12 hours ago, Alan de Enfield said:

My campervan has been away at the local garage having a cambelt and new clutch fitted.

He has had it since mid November and the 'domestic battery' was down to 10 volts, I put it on charge for 3 days and got it back up to 12.8+ but the next day it was down to 11.8 volts.

 

I've had it on charge again today and it has spent several hours at 14.4 volts, so I've now switched it off.

 

Come the morning when it has had chance to stabilise I will start a discharge test using a car headlight bulb (55/65 watt) it'll at least give me an idea of the actual capacity.

@wandering

 

I have this morning done the discharge test and after 2 hours drawing 5 amps the voltage was down to 12.3 volts. The test is 'rough & ready' but gives a good guide to pending troubles.

 

12.3 volts is approximately 65% state of charge, so in 2 hours I used 10Ah and 'used' 35% of capacity.

 

Therefore if 10Ah = 35% capacity the 100% capacity is around 29Ah.

The battery was 'as new' 120Ah so by standing for 3 months partly charged and powering a single USB socket (with a tiny glow) it has lost almost all of its storage capacity.

 

I think you may have similar problems, you need a new battery, AND to learn how to stop it happening again. You can 'kill' a battery in a matter of weeks.

 

 

 

 

Edited March 27, 2023 by Alan de Enfield

[cuthound]

14 hours ago, Alan de Enfield said:

My campervan has been away at the local garage having a cambelt and new clutch fitted.

He has had it since mid November and the 'domestic battery' was down to 10 volts, I put it on charge for 3 days and got it back up to 12.8+ but the next day it was down to 11.8 volts.

 

I've had it on charge again today and it has spent several hours at 14.4 volts, so I've now switched it off.

 

Come the morning when it has had chance to stabilise I will start a discharge test using a car headlight bulb (55/65 watt) it'll at least give me an idea of the actual capacity.

 

I do this with my boats domestic bank every year to discharge to circa 50%. I then enter the revised capacity into the battery monitor and charge until the tail current has dropped to 1% of the batteries capacity at a charging voltage of 14.6 volts. Then I synchronise the monitor state of charge reading and it remains fairly accurate for about 3 months, when I again fully recharge and re-synchronise.

Edited March 27, 2023 by cuthound
Phat phingers

[dmr]

4 hours ago, mrsmelly said:

When I was a kid my Grannie always bought that sterilised milk, iirc it came in taller bottle with a thinner neck lol.

 

Was it a nationwide thing? My parents in Birmingham had sterilised milk (a sort of white water) and I remember lots of unhappiness when they went on holiday and could only get the thick stuff that they hated. I assumed sterilised was a Birmingham/midlands thing???

[Tracy D'arth]

4 minutes ago, dmr said:

 

Was it a nationwide thing? My parents in Birmingham had sterilised milk (a sort of white water) and I remember lots of unhappiness when they went on holiday and could only get the thick stuff that they hated. I assumed sterilised was a Birmingham/midlands thing???

There was The Cheshire Sterilised Dairy in Stockport where Freddie Garrity, of Freddie and the Dreamers, worked before he became famous. Lots of "Sterra" around Manchester because it didn't go off so quickly.

[Mike Hurley]

My nan used to buy that sterilised stuff, i hated it, made my teeth feel strange.

[Tracy D'arth]

I had a foreman who would spend ages brewing up coffee for the lads. He used to boil up sterilised milk whilst stirring in sugar and Camp Coffee, which was chicory extract, and keep it boiling till it thickened. 

If allowed to go cold, it set. You had a limited time to drink it, or, as many did, surreptitiously pour it away.

 

How we got here from duff batteries I don't know, so,       and back to how to charge batteries.

 

I don't think your inverter is faulty. The batteries simply had insufficient capacity to provide the high current needed to heat the blanket ( Electric blanket on a boat, whatever next ) and the inverter shut down with a squawk as it should due to low voltage.  Try it with the engine running and it will likely work if the alternator can provide enough juice. After approximately 10 years the capacity is probably close to nothing.