Cost of rewiring

[George and Dragon]

Not sure I understand the logic there. Is that because of uninsulated tools?

[bizzard]

49 minutes ago, George and Dragon said:

Not sure I understand the logic there. Is that because of uninsulated tools?

Not really. Its because the positive lead once disconnected can flop around and touch any metalwork and arc. Those leads are stiff and if you think you've lodged it safely they can spring away and touch metal and arc.

[Tony Brooks]

1 hour ago, George and Dragon said:

Not sure I understand the logic there. Is that because of uninsulated tools?

Yes, bit hard to get totally insulated spanners/sockets.

 

Not sure what Biz has taken but it seems a bit of good stuff.

 

One the positive or negative battery terminal is disconnected the circuit will be dead, that is open circuit so no current can flow. So even if the positive battery clamp touched metal no current can flow because there is a great big gap between the battery post and what connected to it.

 

Where there may be a danger in the way Biz describes is if you are working on the circuit and the battery lead flopped across to the battery and made contact with the post. Then the circuit would become live so that may cause a problem.

 

 

[bizzard]

15 minutes ago, Tony Brooks said:

Yes, bit hard to get totally insulated spanners/sockets.

 

Not sure what Biz has taken but it seems a bit of good stuff.

 

One the positive or negative battery terminal is disconnected the circuit will be dead, that is open circuit so no current can flow. So even if the positive battery clamp touched metal no current can flow because there is a great big gap between the battery post and what connected to it.

 

Where there may be a danger in the way Biz describes is if you are working on the circuit and the battery lead flopped across to the battery and made contact with the post. Then the circuit would become live so that may cause a problem.

 

 

Yes TB. I had an unusual mental blockage. For some strange reason I was thinking of the other end of the pos cable, at the starter motor or wherever. I need a split charge relay fitting.

Edited August 24, 2018 by bizzard

[George and Dragon]

1 minute ago, bizzard said:

Yes TB. I had an unusual mental blockage. For some strange reason I was thinking of the other end of the pos cable, at the starter motor or wherever. I need a slit charge relay fitting.

That's ok then. I was starting to think I had missed something 

[Tony Brooks]

14 minutes ago, bizzard said:

Yes TB. I had an unusual mental blockage. For some strange reason I was thinking of the other end of the pos cable, at the starter motor or wherever. I need a split charge relay fitting.

Yeh, I reckon we have all done that, so engrossed in the job and working against time and somehow  disconnecting the battery gets forgotten or nowadays trying to do jobs without a memory saver and avoiding erasing the volatile memory in the ECU.

[TheBiscuits]

4 hours ago, LadyG said:

I did suggest something like that to the garage, but he suggested it was not the solution. We have had this problem for two years, five batteries, two alternators, two motherboards and extended periods off road in garage [endeavouring to keeping costs to a minimum, my van is not prioritised] . 

I will put van back on the road if I get some work for it, but best move is to sell it, it keeps going if it gets a nice run every day. Other than that it will get an hour or two every week.

I had a car with a parasitic draw on it, so just added a small solar panel to keep it topped up.  You can get them with a 12V cigar lighter plug.

[bizzard]

9 minutes ago, Tony Brooks said:

Yeh, I reckon we have all done that, so engrossed in the job and working against time and somehow  disconnecting the battery gets forgotten or nowadays trying to do jobs without a memory saver and avoiding erasing the volatile memory in the ECU.

 

9 minutes ago, Tony Brooks said:

Yeh, I reckon we have all done that, so engrossed in the job and working against time and somehow  disconnecting the battery gets forgotten or nowadays trying to do jobs without a memory saver and avoiding erasing the volatile memory in the ECU.

 

10 minutes ago, Tony Brooks said:

Yeh, I reckon we have all done that, so engrossed in the job and working against time and somehow  disconnecting the battery gets forgotten or nowadays trying to do jobs without a memory saver and avoiding erasing the volatile memory in the ECU.

My memory saver is not functioning reliably these days.  And yes, always use a memory saver on modern ECU vehicles before disconnecting the battery, just in case. Or jump leads from another battery clamped to the battery cable clamps of the problem vehicle.

[LadyG]

5 hours ago, TheBiscuits said:

I had a car with a parasitic draw on it, so just added a small solar panel to keep it topped up.  You can get them with a 12V cigar lighter plug.

yes, but it will be fine for a few days, then will discharge a fully charged battery overnight!

Anyway the positive   post had a red plastic hood, and the neg post has sevral wires attached, so I will disco that one.

[Erik.narrowboat]

On 22/08/2018 at 15:12, Tony Brooks said:

 

Get a length of wire of any thickness bare at each end. At a point lose t the alternator push a pin right through the centre of the  blue cable but do not let it touch anything metal. Connect the voltmeter to the engine battery and start the engine and rev to around 1200 to 1500 rpm.  Now touch one end of the wire to engine battery positive and the other end t the pin. The voltmeter should jump up as you did  it. If so the alternator is OK and the problem is the warning lamp circuit.

I have gone back to the first step and test the alternator with the wire.

With the voltmeter attached to the starter battery it reads 12.6 volt. As soon as I start the engine this guess up to 14v. Holding the wire against the battery and the pin that suits through the blue quite still makes it read 14v so no jump.

 

I have printed all of your instructions and read them about five times. I'm trying to follow them closely. I apologize for jumping ahead previously.

You mentioned that looking at the photos makes you lose work, is there a way I can make it easier to read/watch my comments?

[WotEver]

1 hour ago, Erik.narrowboat said:

With the voltmeter attached to the starter battery it reads 12.6 volt. As soon as I start the engine this guess up to 14v. 

Then the alternator is working. Now we need to find out why it isn’t charging the domestics. 

 

That’s assuming that the domestics are indeed flat as you stated. 

[Tony Brooks]

3 hours ago, Erik.narrowboat said:

I have gone back to the first step and test the alternator with the wire.

With the voltmeter attached to the starter battery it reads 12.6 volt. As soon as I start the engine this guess up to 14v. Holding the wire against the battery and the pin that suits through the blue quite still makes it read 14v so no jump.

 

I have printed all of your instructions and read them about five times. I'm trying to follow them closely. I apologize for jumping ahead previously.

You mentioned that looking at the photos makes you lose work, is there a way I can make it easier to read/watch my comments?

The next step was to repeat the test but with the voltmeter on the domestic bank so we can see if that is charging - what is the result?

 

So the alternator appears to be working and energising without a warning lamp. That is wrong unless you revved the engine flat out and even then the alternator often fails to energise so I am afraid more tests are needed once you have confirmed the domestic bank is also charging.  A 14 volt initial charge on a split charge system  is very high if you have flat domestic batteries unless they are so sulphated they are beyond use. It may be time to get one charged and just connect that while we are testing.

 

This test is to see if there is a permeate 12V feed to the D+terminal. If there is then the engine battery is likely to go flat within a very few days unless soem clown has fed the instrument from the domestic bank but your comments do not support that..

 

Pin back in D+ cable

Voltmeter between pin and any clean metal or battery negative - note reading, should be zero. If battery voltage its a fault so report back.

 

Repeat with the ignition turned on - note reading, it should be all but zero, report result.

 

Remove pin.

 

It would help if you emailed me the photos so I can look a them without scrolling back through the topic, Tony@tb-training.co.uk , but I think I have  got most of them in my head.

 

 

 

 

 

[Erik.narrowboat]

56 minutes ago, Tony Brooks said:

The next step was to repeat the test but with the voltmeter on the domestic bank so we can see if that is charging - what is the result?

 

So the alternator appears to be working and energising without a warning lamp. That is wrong unless you revved the engine flat out and even then the alternator often fails to energise so I am afraid more tests are needed once you have confirmed the domestic bank is also charging.  A 14 volt initial charge on a split charge system  is very high if you have flat domestic batteries unless they are so sulphated they are beyond use. It may be time to get one charged and just connect that while we are testing.

 

This test is to see if there is a permeate 12V feed to the D+terminal. If there is then the engine battery is likely to go flat within a very few days unless soem clown has fed the instrument from the domestic bank but your comments do not support that..

 

Pin back in D+ cable

Voltmeter between pin and any clean metal or battery negative - note reading, should be zero. If battery voltage its a fault so report back.

 

Repeat with the ignition turned on - note reading, it should be all but zero, report result.

 

Remove pin.

 

It would help if you emailed me the photos so I can look a them without scrolling back through the topic, Tony@tb-training.co.uk , but I think I have  got most of them in my head.

 

 

 

 

 

The domestic bank reads 0, when I hold the meter between battery positive and the pin it still reads 0.

 

The wires from the alternator are connected to starter battery positive. They were previously on the domestic bank but since that is flat another electrician moved them here.

 

Voltmeter between clean metal and pin with ignition off gives 0 volt. With ignition on it gives about 2 volt.

 

I have attached two photos. One shows the starter battery positive with two thick red wires from the alternator connected. The other shows how the domestic bank is wired. Both positive and negative go to the electric cupboard, separate from the starter battery.

 

I have bought a new domestic battery because I figured I would need it at some point. Should I install it and repeat the the first test?

 

I will also send you the photos along with previous ones by email.

 

 

[Tony Brooks]

2 hours ago, Erik.narrowboat said:

The domestic bank reads 0, when I hold the meter between battery positive and the pin it still reads 0.

 

The wires from the alternator are connected to starter battery positive. They were previously on the domestic bank but since that is flat another electrician moved them here.

 

Voltmeter between clean metal and pin with ignition off gives 0 volt. With ignition on it gives about 2 volt.

 

I have attached two photos. One shows the starter battery positive with two thick red wires from the alternator connected. The other shows how the domestic bank is wired. Both positive and negative go to the electric cupboard, separate from the starter battery.

 

I have bought a new domestic battery because I figured I would need it at some point. Should I install it and repeat the the first test?

 

I will also send you the photos along with previous ones by email.

 

 

.

.

 

I would advise against installing the new domestic battery until we get the charging sorted.

 

I think you misunderstood the domestic battery test I asked you to do.

 

It seems the alternator is generating from the moment the engine revs and without a voltage on D+ (Blue wire on small blade) it should not without a warning lamp but you do have that 2V so the question is where is this coming from. That explains why the alternator energised but without lighting the bulb but I can't work out where it is coming from. So as the B+ and D+ blades are close together please pull the D+ terminal out of the alternator and wrap a couple of turns of insulating tape around the exposed part of the female blade on the end of the wire and refit. This will prevent any odd effects that may be caused if D+ and B+ touch each other.

 

The test I wanted you to do was to put the volt meter across the domestic battery and start and rev the engine. It should jump up as the alternator energises and if it does not then the relay is suspect. For now I intend to ignore the warning lamp and where the feed to D+ is coming from because at least it seems the alternator is charging. So what does the voltmeter across the domestic battery do when you start and rev the engine?

 

If it does not jump up but the voltage on the engine battery does it suggest the relay or its wiring is faulty. To test this pull the two LARGE terminals off the relay and join the two terminals you removed. As you join the the domestic battery voltage should jump up. If it does it means we have to find out why its not working. Is it a relay or wiring fault? Deciding that involves more tests but we can go into that when we know what happens at the domestic battery.

 

 

Those two thick red wires from the alternator are fine for now on the engine battery but to maximise the relay's life we will eventually put them back on the domestic battery when all else is sorted. In fact whoever fitted two wires did a far better job than on many such alternators that only have one wire and consequently tend to overheat the terminal in the alternator, so that's a plus. Even if the domestic batteries were flat moving those wires to the engine battery would not alter the alternator’s ability to produce a charge but it would help keep the engine battery charged if the relay was not making contact..

 

[Erik.narrowboat]

I have insulated the D+. I noticed the other wires are corroded and also quite dirty. Do you think this might have an effect?

 

Voltmeter across domestic battery reads 0, with engine off and with engine on. To be sure I moved the wires to the engine battery with the engine running and that still measured 14v, meaning the alternator is working. I then moved the wires back to the domestic battery and connected the two thick cables from the relay, but the reading showed 0v.

 

 

[Sea Dog]

2 minutes ago, Erik.narrowboat said:

I noticed the other wires are corroded and also quite dirty. Do you think this might have an effect?

Yes. Yes! Yes!!  

 

Have you really not cleaned all that filthy wiring up yet, wiped the crud off the top of that gopping battery and made good ALL those scabby connections?  It's fundamental and I'd suggest everything else you're trying to do should be done only after doing this.  Bad connections and dirt allowing leakage could be affecting everything, even if it's not the root cause of some of your issues. Plus, if someone comes to help, it'll at least look like you care - and who'd really want to help someone who didn't?

 

 

[bizzard]

1 hour ago, Erik.narrowboat said:

I have insulated the D+. I noticed the other wires are corroded and also quite dirty. Do you think this might have an effect?

 

Voltmeter across domestic battery reads 0, with engine off and with engine on. To be sure I moved the wires to the engine battery with the engine running and that still measured 14v, meaning the alternator is working. I then moved the wires back to the domestic battery and connected the two thick cables from the relay, but the reading showed 0v.

 

 

 

If it was the main B+ cable from the alternator that you were disconnecting and re-connecting between batteries while the engine was running you are lucky the alternator is still working, always switch off the engine before disconnecting that cable.

[Tony Brooks]

2 hours ago, Erik.narrowboat said:

I have insulated the D+. I noticed the other wires are corroded and also quite dirty. Do you think this might have an effect?

 

Voltmeter across domestic battery reads 0, with engine off and with engine on. To be sure I moved the wires to the engine battery with the engine running and that still measured 14v, meaning the alternator is working. I then moved the wires back to the domestic battery and connected the two thick cables from the relay, but the reading showed 0v.

 

 

 

 

1. Please do not go trying to replace the terminals. At this stage the last thing we need is for you to build another fault into the system.  We are working on voltages at present and the 14V shoes the connections are good enough for now. You can sort  the terminals  and corrosion later.

 

2. I read your second paragraph to say you simply charged the meter leads from engine to domestic battery and if so there is no danger to the alternator BUT take note of what Bizzard says. Do not disconnect wires or turn the master switch off when the engine is running.

 

3. Your test above confirms the alternator is proving a charge but the charge is not getting to the domestic bank so we need the result of this test: If it does not jump up but the voltage on the engine battery does it suggest the relay or its wiring is faulty. To test this pull the two LARGE terminals off the relay and join the two terminals you removed. As you join the the domestic battery voltage should jump up. If it does it means we have to find out why its not working. Is it a relay or wiring fault? That I put into my last message,

 

I have blown the photo of the blue relay up and it looks as if it has too many wires on for a split charge relay and at least one wire is not thick enough but I still think it will have two larger blade terminals. If so pull the wires off then and join the two female blades together. You can often do this by sliding one side of the female terminal into the side of the other. Then start & rev the engine and see if the voltage on the domestic bank rises.

 

IF there is a little diagram on the side of the relay can you send a photo of it please and if not try to photo the base where the wires connect, there should be numbers on the base or send a diagram.

 

The lack of two thick wires on that relay makes me think that we are getting very close to the time we need to fit another one. I would advise a Voltage Sensitive Relay because it makes wiring it a lot easier and it will charge both batteries from a mains charger or solar if you fit them in the future. I think that I may never be able to work out how the boat is wired  from a distance. This is the one I fitted last winter: https://www.amazon.co.uk/140amp-Cargo-voltage-sensitive-SCR008/dp/B01NC3ESP3/ref=sr_1_9?ie=UTF8&qid=1535394180&sr=8-9&keywords=VSR

I think that you will need at least some thick wire (say) 8.5 or 10 sq mm Conductor Cross sectional area plus some decent ratchet crimper and crimp terminals to connect it into the system but wait until I feel we cant investigate the relay thing any further.

 

Remember we will also need to address the warning light issue that is far from being solved and again I suspect that will require rewiring. I will tackle that once we get the split charge working.

 

 

 

[Erik.narrowboat]

20 hours ago, bizzard said:

If it was the main B+ cable from the alternator that you were disconnecting and re-connecting between batteries while the engine was running you are lucky the alternator is still working, always switch off the engine before disconnecting that cable.

I meant the wires from the voltmeter. Sorry if that was unclear.

[Erik.narrowboat]

18 hours ago, Tony Brooks said:

 

1. Please do not go trying to replace the terminals. At this stage the last thing we need is for you to build another fault into the system.  We are working on voltages at present and the 14V shoes the connections are good enough for now. You can sort  the terminals  and corrosion later.

 

2. I read your second paragraph to say you simply charged the meter leads from engine to domestic battery and if so there is no danger to the alternator BUT take note of what Bizzard says. Do not disconnect wires or turn the master switch off when the engine is running.

 

3. Your test above confirms the alternator is proving a charge but the charge is not getting to the domestic bank so we need the result of this test: If it does not jump up but the voltage on the engine battery does it suggest the relay or its wiring is faulty. To test this pull the two LARGE terminals off the relay and join the two terminals you removed. As you join the the domestic battery voltage should jump up. If it does it means we have to find out why its not working. Is it a relay or wiring fault? That I put into my last message,

 

I have blown the photo of the blue relay up and it looks as if it has too many wires on for a split charge relay and at least one wire is not thick enough but I still think it will have two larger blade terminals. If so pull the wires off then and join the two female blades together. You can often do this by sliding one side of the female terminal into the side of the other. Then start & rev the engine and see if the voltage on the domestic bank rises.

 

IF there is a little diagram on the side of the relay can you send a photo of it please and if not try to photo the base where the wires connect, there should be numbers on the base or send a diagram.

 

The lack of two thick wires on that relay makes me think that we are getting very close to the time we need to fit another one. I would advise a Voltage Sensitive Relay because it makes wiring it a lot easier and it will charge both batteries from a mains charger or solar if you fit them in the future. I think that I may never be able to work out how the boat is wired  from a distance. This is the one I fitted last winter: https://www.amazon.co.uk/140amp-Cargo-voltage-sensitive-SCR008/dp/B01NC3ESP3/ref=sr_1_9?ie=UTF8&qid=1535394180&sr=8-9&keywords=VSR

I think that you will need at least some thick wire (say) 8.5 or 10 sq mm Conductor Cross sectional area plus some decent ratchet crimper and crimp terminals to connect it into the system but wait until I feel we cant investigate the relay thing any further.

 

Remember we will also need to address the warning light issue that is far from being solved and again I suspect that will require rewiring. I will tackle that once we get the split charge working.

 

 

 

I am a little bit confused as to whether the message I wrote yesterday had displayed correctly. I was having some issues uploading an image. I will post it again below.

 

To answer to your message.

1. Sure, I will wait.

2. That is correct, I have but been moving wires with the engine running, other than those from the voltmeter.

3. I have taken off the to large blades from the relay and then, after starting the engine, made them touch. The image below shows the two thick cables disconnected.

 

If this photo is not clear enough (it was meant to show the wires), I can take a more close up one of the relay when I get home.

 

Should I order the relay you have shown or wait?

[WotEver]

21 hours ago, Erik.narrowboat said:

connected the two thick cables from the relay, but the reading showed 0v.

With the engine running connect one lead from the voltmeter to one of those thick wires and the other lead to the hull. Then try the other thick lead (in fact you might as well do all of the relay cables one at a time). Report back which if any have 14V on them. 

1 hour ago, Erik.narrowboat said:

Should I order the relay you have shown or wait?

Wait

[Tony Brooks]

Erik, did the domestic battery voltage rise when you touched those two big terminals? I do not see an answer to that question.

 

If it did not then there is a wiring fault, if it did the relay is faulty or there is something wrong with the wiring to energise it.  As the two wire colours other photos indicate might energise it are blue or brown and there are no brown wires there I suspect the wiring even if the relay is not faulty

 

If the relay is faulty you need to decide if you want another ordinary split charge relay that will involve you making and running two thick red wires plus a thin other than black colour plus a thin black one. The thin "other than black" one can be run from the charge warning lamp that will also need to be fixed or the D+ on the alternator.

 

If you decide on a VSR like I showed you then you will need to run two thick red wires and one thin black wire and leave sorting the warning light until we get bot batteries charging.

 

 

Sorting the warning lights is going involve some rewiring and although you can loop cables from instrument to instrument and to warning lamps it is probably easier if you stick with one wire for one job so that will involve what we call a bus bar. It also make s fault fining simpler. The bus bar is nothing difficult or expensive. The one I Ludlow suggest you screw under the instrument panel is this one http://www.vehicle-wiring-products.eu/product.php/338/3-x-6-way-terminal-block or similar. It will allow you to run 5 negatives and five positiver with a spare set of blades between them to keep the wires apart and they take crimp blade terminals to make fitting  a little easier. I mention this now so if you buy mail order you can get both and hopefully only pay one lot of postage.

 

You will also need maybe three metres of 8.5 or 10 sq mm conductor cross sectional area with suitable terminals for the job and ratchet crimp tool. A similar amount of 1 or 2 sq mm CCSA black cable. If you elect to go for a split charge relay then several meters of similar thin cable in another colour, all plus suitable terminals, and thin zip ties to fit keep the new cables secure. If it is all to come from the same place then a red plus an amber warning lamp.

 

You do not have to buy its all at once because we can do it step by step.

 

[Tony Brooks]

Some further information. I am about 98% sure that relay has an extra terminal that is used to supply an electric fridge (old 3 way type) when the engine of the CA was running while driving to a caravan site. In a boat installation this is not required so would normally be left disconnected. One thing it would not have on it is a negative cable and typically negative cables are black. It looks as if a tinkerer has been at the boat.

 

here is a photo and the pin diagram for it:

 

 

Pin 2 would come from the engine or domestic battery positive, thick wire. 

Pin 5, again with a  thick wire, will come from the other battery positive.

Pin 1 will come from D+ in some way.

Pin 3 will come from any negative.

The wiring on pins 1 & 3 be transposed

Pin 4 is left with no connection.

Edited August 28, 2018 by Tony Brooks

[WotEver]

1 hour ago, Tony Brooks said:

Erik, did the domestic battery voltage rise when you touched those two big terminals? I do not see an answer to that question.

 

On 27/08/2018 at 16:27, Erik.narrowboat said:

I then moved the wires back to the domestic battery and connected the two thick cables from the relay, but the reading showed 0v.

 

[Tony Brooks]

I don't understand this moving wires bit UNLESS Erik means he moved the meter to the domestic bank. If so then the wiring is at fault and I think a new VSR and wiring will be the easiest way forward but its his call. goodness knows where those two thicker wires come from though. Your test about three posts above might give a clue but I am getting ready to simply replace them so we know what is going on..