Cost of rewiring

[MtB]

2 hours ago, Erik.narrowboat said:

I just called the electrician who came yesterday for a quote for just rewiring the engine room.

 

I think you're still not directing your tradespeople very competently. Why did you ask for an engine room re-wire? Your engine room seems to have expensive stuff (inverter and 240v wiring) unrelated to the engine failing to start. 

 

My I suggest you should have said something along the lines of "my engine won't start and when it did run, these wires keep coming adrift. Can you fix this please?"

 

The inverter is a complete red herring. Don't even discuss it with them. Your priority needs to be getting the engine starting and charging the start battery. Once that is fixed, THEN move on to domestic wiring as a whole different project.

[Erik.narrowboat]

I actually told the electrician to bit worry about the inverter for now. But I take your point that my instructions have to be clear in other to get the job done. I was advised rewiring of the engine room by several people, also a retired mechanic who has no financy interest in recommending me expensive repairs. There are a few things that are wrong with the wiring, fire example the engine electrics were connected to the leisure battery.

 

Something I was thinking about yesterday. I am planning to buy solar panels. The ones I have now are small and cheap ones so I'll have to get some proper ones. If I would install those that would keep my batteries charged. I could then use my water pump and the lights which shouldn't be too much. I can do without the fridge or other electronics for now. Does that make sense or may i run into other problems?

[Alan de Enfield]

4 minutes ago, Erik.narrowboat said:

I could then use my water pump and the lights which shouldn't be too much. I can do without the fridge or other electronics for now. Does that make sense or may i run into other problems?

It very much depends on 'how much' you have to spend and how large a solar array you intend to install.

 

Sufficient (amount to be decided) solar will 'keep you going' for (approximately) 5 months of the year - come September & October it will not be enough, come November to Feb it will produce 'nothing' then start to produce (not enough) in March & April.

 

Solar is not a panacea for all electrical problems.

[Erik.narrowboat]

Most boats seem to have two panels which I think totals about 3m2. I think they would cost a couple of hundreds. I know they won't solve everything but they should produce a reliable charge in the next couple of months to keep my batteries from going flat. That means I can slowly start solving all the other issues.

 

Separate question, would Canal and river rescue be able to help me? Or are they there just fur emergencies?

[Alan de Enfield]

6 minutes ago, Erik.narrowboat said:

Most boats seem to have two panels which I think totals about 3m2. I think they would cost a couple of hundreds.

On one of my boats I have 3x 100 watt panels, and on the other 1x 170 watt panel. Neither give sufficient battery charging for my needs.

Have a scan around this website (and remember it is not just panels you need, but a MPPT controller mountings, cables clips, etc etc)

 

This shows the cost of a complete 2x 100 watt panel 'kit' at £480

 

https://www.bimblesolar.com/offgrid/12v?product_id=1256

 

You can get away without some of the 'stuff' but that is ideally what you will need to install it properly and safely.

[Erik.narrowboat]

Thanks for the link. I am willing and able to pay this kind of amount to get good quality panels. Do you reckon these are good quality?

Can I ask you what you are running? Fur me it will be fridge, water pump, lights, phone and perhaps laptop. I do not own a TV and don't really just the microwave.

[TheBiscuits]

5 minutes ago, Erik.narrowboat said:

Thanks for the link. I am willing and able to pay this kind of amount to get good quality panels. Do you reckon these are good quality?

Can I ask you what you are running? Fur me it will be fridge, water pump, lights, phone and perhaps laptop. I do not own a TV and don't really just the microwave.

https://www.bimblesolar.com/offgrid/12v/305W-kit-mppt-mounting

 

That's a bigger solar kit for less money.  Depends if you have roof room to fit it though.

[Alan de Enfield]

11 minutes ago, Erik.narrowboat said:

Thanks for the link. I am willing and able to pay this kind of amount to get good quality panels. Do you reckon these are good quality?

Can I ask you what you are running? Fur me it will be fridge, water pump, lights, phone and perhaps laptop. I do not own a TV and don't really just the microwave.

No problem :

 

12v Fridge, Freezer (Via Inverter), phone charging, laptop charging, pumps, lights etc,

 

I have found as a rough guide you can use the following for estimating what you will (in the real world) get out of panels

 

Summer (5-months) = 50% of theoretical

late Spring / Early Autumn = 25% of theoretical

Late Autumn / Winter / Early spring - 0% to 5% of theoretical

 

The theoretical outputs are based on the sun directly over head in the tropics (so it doesn't have to travel so far) we are at Northern latitudes and that has a big reduction factor in output as the angle of incidence is much lower, add in a few clouds and the odd overcast / rainy day  (yes - even in Summer) and the output drops way-down.

 

In theory you should get around 8 amps from a 100 watt panel for (say) 12 hours on a Summers day so that is about 96Ah per day.

I have found (as I say) that 50% is more realistic so I work on getting (in the height of Summer) about 45Ah per day.

During the Summer I average about 120-130Ah out of my 300w of panels

 

A 12v Fridge will use (depending on make / type / model) between about 30 and 50Ah per day.

 

You can either modify you electrical usage to match your panels output, or match your panels to your electrical usage.

 

Have you undertaken an electrical audit yet ? (multiply how much electric EVERYTHING uses, by the amount of time it runs)

 

Edited July 28, 2018 by Alan de Enfield

[Erik.narrowboat]

Thanks. I'll try to do an audit asap.

 

I just measured my starter battery and it is at 11.79 volts. I think this is still a little low? But it was all the way down to 7 so it's good news, I going to try starting the engine tomorrow. At least charging it with the little solar panel seems to work

[TheBiscuits]

4 minutes ago, Erik.narrowboat said:

Thanks. I'll try to do an audit asap.

 

I just measured my starter battery and it is at 11.79 volts. I think this is still a little low? But it was all the way down to 7 so it's good news, I going to try starting the engine tomorrow. At least charging it with the little solar panel seems to work

It's dead. 

 

"'E's not pinin'! 'E's passed on! This parrot battery is no more! He has ceased to be! 'E's expired and gone to meet 'is maker! 'E's a stiff! Bereft of life, 'e rests in peace! If you hadn't nailed 'im to the perch 'e'd be pushing up the daisies! 'Is metabolic processes are now 'istory! 'E's off the twig! 'E's kicked the bucket, 'e's shuffled off 'is mortal coil, run down the curtain and joined the bleedin' choir invisible!! THIS IS AN EX-parrot battery !!"

 

Disconnect the little solar panel and it will drop right back down again.

 

You are measuring the solar panel voltage, not the battery voltage.

Edited July 28, 2018 by TheBiscuits

[rusty69]

8 minutes ago, TheBiscuits said:

It's dead

The parrot "jokes" are on the other thread, biscuits :

 

 

 

[Erik.narrowboat]

Oh, didn't think about that. You're sure it's dead because it's been down to 7? I was told a new battery cash recover from there.

[nicknorman]

17 minutes ago, Erik.narrowboat said:

Oh, didn't think about that. You're sure it's dead because it's been down to 7? I was told a new battery cash recover from there.

Recover with some loss of capacity if recharged immediately. If left, recover with a major loss of capacity. As I tried to explain earlier, anything below about 12.7v means it isn’t fully charged. Anything below about 12.2v means it needs to be recharged immediately. Once below 12v it is flat, and rapidly accumulating damage with time. I know it is called a “12v battery” but I suspect you are thinking of it being full at 12v and flat at zero v. You need to adapt your thinking, it isn’t like that!

[MtB]

2 hours ago, nicknorman said:

Recover with some loss of capacity if recharged immediately. If left, recover with a major loss of capacity. As I tried to explain earlier, anything below about 12.7v means it isn’t fully charged. Anything below about 12.2v means it needs to be recharged immediately. Once below 12v it is flat, and rapidly accumulating damage with time. I know it is called a “12v battery” but I suspect you are thinking of it being full at 12v and flat at zero v. You need to adapt your thinking, it isn’t like that!

 

 

Even so, a 12v starter battery sulphated down to say 50% of badge capacity and only half charged will happily deliver enough energy to start the engine.

[David Mack]

3 minutes ago, Mike the Boilerman said:

 

 

Even so, a 12v starter battery sulphated down to say 50% of badge capacity and only half charged will happily deliver enough energy to start the engine.

...on a warm day.

Just don't try it when the cut is frozen, and the engine oil is the consistency of cheese.

[MtB]

Just now, David Mack said:

...on a warm day.

Just don't try it when the cut is frozen, and the engine oil is the consistency of cheese.

 

It only takes about 1AH to start a typical boat diesel engine.

[nicknorman]

10 minutes ago, Mike the Boilerman said:

 

 

Even so, a 12v starter battery sulphated down to say 50% of badge capacity and only half charged will happily deliver enough energy to start the engine.

True, but we are talking about much more than 50% loss of badged capacity.

[MtB]

7 minutes ago, nicknorman said:

True, but we are talking about much more than 50% loss of badged capacity.

 

How do you know? How much more than 50% is lost?

 

Has someone run a capacity test on this (new but uncharged) battery?

 

 

 

My estimate on the available evidence is 50% down.

[nicknorman]

14 minutes ago, Mike the Boilerman said:

 

How do you know? How much more than 50% is lost?

 

Has someone run a capacity test on this (new but uncharged) battery?

 

 

 

My estimate on the available evidence is 50% down.

In my experience it is very easy to lose 50% capacity even when you think you are being kind to your batteries. Taking a battery down to 7v and leaving it thus for days isn’t being kind.

Edited July 28, 2018 by nicknorman

[MtB]

1 minute ago, nicknorman said:

In my experience it is very easy to lose 50% capacity even when you think you are being kind to your batteries. Taking a battery down to 7v and leaving it thus for days isn’t being kind.

 

Even so, I bet once recharged to 12.7v it will be capable of starting the OP's engine.

[nicknorman]

4 minutes ago, Mike the Boilerman said:

 

Even so, I bet once recharged to 12.7v it will be capable of starting the OP's engine.

It might be, if it’s a reasonably good starter. But its life and capacity will have been seriously shortened. My point was to explain to the OP that it is no way to treat a battery. It is a shame that you attempt to undermine that.

[MtB]

5 minutes ago, nicknorman said:

It might be, if it’s a reasonably good starter. But its life and capacity will have been seriously shortened. My point was to explain to the OP that it is no way to treat a battery. It is a shame that you attempt to undermine that.

 

I'm sure he's got the message. I attempting to undermine the posters who were working around to saying it is useless and must be replaced. I hold this is not necerssarily true and a sulphated starter battery may work just fine for a while yet. 

[TheBiscuits]

19 minutes ago, Mike the Boilerman said:

 

I'm sure he's got the message. I attempting to undermine the posters who were working around to saying it is useless and must be replaced. I hold this is not necerssarily true and a sulphated starter battery may work just fine for a while yet. 

Assuming you mean me Mike, I'll bite.  If only Erik had a "fuel gauge" for his batteries, eh

 

The knackered battery *might* start the boat in 20C+ temperatures.  I don't think it will continue to do so into autumn, and I think that Erik should assume it is bust, and budget for a replacement.

 

I was highly suspicious of the battery state once he told us that he could jump start the boat despite the wiring issues and everything he has added since makes me think he needs a new starter battery, and probably a new domestic bank.

 

If he can afford it, I think adding at least 300W of solar will help him immensely for the next few months. 

 

I think we should also point out that any half-competent auto electrician will be able to sort him out, even if they have never seen a boat before!  Engine start electrics are pretty simple on basic diesels, in fact the comment earlier was seven wires including an isolator switch.

 

There is an old saying that most boat electrical problems are fixable if you can start the engine, and it is very true.

 

 

[Erik.narrowboat]

I'm aware batteries have to be charged reliably and running it down to 7v is definitely not good. It's kind of the whole problem that I don't know if the batteries are charging. I therefore haven't installed new leisure batteries because they will just discharge and then I can throw them. I needed to install the new starter battery though to be able to test what parts work or not. Without any current there would simply be nothing to look at. Unfortunately it discharged quite a lot, I'm not sure why it went down to 7 because I only started the engine once as a test. Perhaps it was drained by the leisure batteries because the relay is not up to the job. This is kind of the whole problem, it's a bit chicken and egg because I need to install batteries to check what works but if I do it wrongly I'll break them. That's why I thought solar panels would help because they will charge the batteries.

I think I need a step by step approach to make the necessary fixes. If anyone can explain what steps to take that would be great. I guess installing a proper relay will never hurt, neither will solar panels. TNG new leisure batteries perhaps?

[Tony Brooks]

I described to you many posts ago how to test your relay but if that is beyond you simply disconnect and insulate one of the thick wires. Take care not to let it or any tools you use touch metal while doing so. Once that is done the normal link between engine & domestic bank is broken so if the engine battery is then discharging into the domestics there is another fault.

 

I also gave you a link to instructions on using a multimeter.

 

Do not spend money on things unless you are sure they are faulty, you will probably need lots to replace faulty batteries! For now & until you get the charging & starting sorted I would not buy any more solar panels as the one you have (about half a sq. metre you said) is probably about 30 watts and should do for now but NOT if it is not connected to a controller

 

1. Carefully squeeze the female blade connectors that keep falling off so they are a tighter fit and replace.

2. When starter battery is charged (even take it to a garage and ask them to charge it for you) put it in place and connect the positive terminal.

3. Connect meter set to 20 volts DC on the domestic battery terminals. From what you say I expect it to read below 12V. Leave it connected.

4. While observing the meter put the engine battery negative terminal onto post and twist a little. The voltmeter reading should not alter. If it goes up you know there is another link between banks somewhere. If the reading stays the same you then know there is on link.

5 Without altering anything reconnect the thick lead to the split charge diode. If the voltmeter rises you know the relay is permanently closed so a  new one is needed. If the reading stays the same you know the relay is open.

 

To further test the relay if it tested as open:

 

6. Start and rev the engine. The voltmeter (on the domestic bank should rise but that will not prove the relay is working, it will just prove the alternator is working and is connected in some way to the domestic batteries so note the reading.

7. Stop engine and move the voltmeter to the engine battery

8. Restart and rev engine, note the meter reading. It should rise to pretty much the same reading that you got in 8 above.  If both readings are the same then the relay is working. If the reading on one battery did not rise when you revved the engine then the relay is stuck open.

 

I am still far from convinced that there is much wrong with the electrics apart from visually horrible wiring AND a dodgy set of domestic batteries that were probably sold to you with the boat. I get the impression that you have just bought the boat and have been having electrical problems ever since.

 

Once you prove to yourself the batteries are not discharging into each other then you can extend those cables and move onto the next problem but until you get to grips with using a meter you will always be paying out for silly electrical problems.

 

When you have done the above report back on what each step told you. The engine should then  start & run  reliably so we can move onto testing the alternator and domestic bank BUT that will only be an indicative test  without a high current ammeter - not the one on the multimeter.