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8 minutes ago, dmr said:

 

Sorry, just about to buy 4 new Trojans to replace the 4 of my 6 that are now over 6 years old. Trojans work for me and a like for like replacement is good because I have other projects going on at the moment. Will probably go Lithium next time but not sure that either me or the canal system will last another 6 years.

I have posted in another thread that I just might supplement the Trojans with a 48 volt lithium bank to replace the Travelpower, but at present my project list is full 😀

 

Tell me again...how many hours did you spend designing and building your own alternator controller and battery management system? 😀😀😀

Quite a lot. But it was worth it. Remember that LA batteries are like naughty children, they need to be fed (with current) but they do everything they can to resist actually eating the current. I’ve come to the conclusion it’s an attention-seeking thing.

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9 minutes ago, nicknorman said:

Quite a lot. But it was worth it. Remember that LA batteries are like naughty children, they need to be fed (with current) but they do everything they can to resist actually eating the current. I’ve come to the conclusion it’s an attention-seeking thing.

and given lots of drinks of magic water.

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10 hours ago, davidb said:

Because the alternator voltage is being reduced by the diode and the Adverc is not compensating for it, even when the sense wire is connected on the battery side of the diode.

 

"do you know about positive and negative rotor control?" Obviously not, maybe the new alternator I got last year was modified wrongly?

 

So after about an hour or so, longer with very discharged or faulty batteries there are no signs of the charging voltage and current moving up and down at roughly 20  minutes high and then 20 minutes low.

 

The sense wire would normally be connected to a domestic battery, not the diode, but I doubt that would stop the Adverc working.

 

In view of how you seem to have the diode wired I think that there might be a mistake in the Adverc wiring so please double-check that it is as Adverc say it should be. I also don't know why you persist with a split charge diode when a VSR and a small rewire would do away with any volt drop problems (as long as the charging cables are large enough and all connections are good).

 

The alternator's own regulator can be placed in the circuit on the positive side of the rotor or the negative, most probably have it in the negative. That is between the rotor and the case/negative. The Adverc is T'd into that circuit between the rotor and the alternator's own regulator. Now the more complicated bit. With discharged batteries when you first start and rev the engine the alternator's regulator will just sit there acting like a closed set of contacts so the voltage on that green fly-lead should be zero or very close to it with the meter between the fly-lead and negative. Once the batteries are charged enough for the alternator's regulator to starts working  it keeps turning itself on and off at a maybe 160 times a second. It alters the mark-space ratio (turned on - turned off) of the connection to negative to control the average current in the rotor and thus the output. What this means is that the voltage on the fly-lead could be anything between zero (regulator conducting) and battery voltage (regulator off). No electricity ever goes into the fly-lead.

 

Now what the Adverc does: At first start up the Adverc is probably acting just like the alternator's regulator, that is fully turned on so the rotor carries its maximum current, but at that stage the alternator is working flat out with the high current depressing the voltage (that's just the way alternators work). Eventually the alternator's regulator will start trying to regulate the rotor current but at this point the Adverc is still conducting the full rotor currant to negative so the charging voltage continues to climb until the Adverc regulation voltage is reached. At that point the  Adverc starts turning the rotor current on and off but at a higher voltage than the alternator's regulator. It will do this for 15 to 20 minutes  and then turn itself off for  15 to 20 minutes, leaving the alternator's regulator to do the voltage regulation.

 

If regulated voltage is never reached for some reason the Adverc can do nothing. It will just sit there.

 

Now, as long as your alternator is negatively regulated, it is vital you  check, you can temporally connect the fly-lead to negative with the engine running with well charged batteries and the charging voltage should go jump up. Make sure all 12V equipment is turned off because you could easily get 20v or more until you disconnect that lead. If that happens the alternator is fine and if when the fly-lead is reconnected the charging voltage does not rise and fall at 15 to 20 minute intervals the Adverc is wrongly wired, faulty, or for some reason the Adverc set voltage is too low.

 

If the regulation is in the positive side I would expect charging voltage on the fly-lead until the regulator started regulating and then the voltage will vary according to the way the regulator is working. Now a bit I am less sure of.  In the case of positive regulation I think that with the engine running and well charged batteries the output would go uncontrolled if you connected the fly-lead to battery voltage. I think in that case putting a variable voltage into the fly-lead might do what you seek, but it won't work on a negative regulation circuit.

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1 hour ago, Tony Brooks said:

So after about an hour or so, longer with very discharged or faulty batteries there are no signs of the charging voltage and current moving up and down at roughly 20  minutes high and then 20 minutes low.

 

Thanks, Tony for an easy -to - understand explanation, I'll go through it all later and ring the people who modified the alternator.

 

No, I have been watching for the Adverc cycling it, but it doesn't.

 

It must be a negative controlling Adverc according to its label:

 

adverc.jpg.1ee8c68494d33b52c97d3d5e4c85e3b0.jpg

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39 minutes ago, davidb said:

 

Thanks, Tony for an easy -to - understand explanation, I'll go through it all later and ring the people who modified the alternator.

 

No, I have been watching for the Adverc cycling it, but it doesn't.

 

It must be a negative controlling Adverc according to its label:

 

adverc.jpg.1ee8c68494d33b52c97d3d5e4c85e3b0.jpg

 

I agree, negative controlled, so should be OK to carefully short that fly-lead to the alternator case with the engien running while watching the battery voltage.

 

Once the Adverc is working you can persuade it to boost the charging voltage by putting a couple of diodes is series in the sense lead. That will boost the charging voltage but might either illuminate an over voltage warning lamp or the Adverc may shut down. Possibly easier than tweeking the Averc motherboard.

 

This may help you sort things out if you do not have the original manual:

 

http://fullsail.done-that.com/Docs/8. Boat Documentation/4. Manuals/Adverc_installation_basic.pdf

 

I think that you will see their diagram for a split charge diode is different to the way yours is wired but I think, with a bit of guessing as to where the cables go, yours  should work. It does mean that one can't be sure about any of the wiring.

Edited by Tony Brooks
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To repeat wot Tony said, if the Adverc is set to a lower voltage than the alternators internal regulator then it will do nothing because it can only increase the voltage.

Trojans like about 14.8 volts so the Adverc should provide this during the high part of its cycle.

 

Its relatively easir to get into the Adverc and adjust the voltage but this will require breaking any seals, no big deal if its already out of warantee.

The Adverc should have its own indicator lamp in addition to the standard ignition lamp. This should be on before the engine starts and will flash to indicate (some) faults.

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21 minutes ago, dmr said:

The Adverc should have its own indicator lamp in addition to the standard ignition lamp. This should be on before the engine starts and will flash to indicate (some) faults.

Yes, it does have one and it acts just like the ignition lamp, and it is the left hand lamp on the box I added with the bypass relay below, and the one thing that changed when I fitted it was that the alternator kicks in immediately the engine starts rather that as it was before when I had to rev it a bit to clear the ignition light:

 

 

diode.jpg

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6 minutes ago, davidb said:
33 minutes ago, dmr said:

 

Yes, it does have one and it acts just like the ignition lamp,

 

I have a feeling that means it is an old Adverc. I think on mine (about 2001) it stayed off unless there was a fault. I only saw mine on once when a field diode fault sent the voltage too high. Maybe the Adverc has died of old age but if it were mine and all the wiring is as per the diagrams I would see if I could get the board out of the thing and try to resolder all the pads to the pins. There is a chance a joint has just broken with age. Low lead solder is known to be prone to that.

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7 hours ago, Tony Brooks said:

you can temporally connect the fly-lead to negative with the engine running with well charged batteries and the charging voltage should go jump up

 

When I get back to the boat I shall disconnect this fly lead and measure the voltage on it with engine running through start-up to full voltage, that might tell me which side of the rotor it is connected.

 

The red Adverc sense lead is extended right the way to the battery + terminal.

 

I have rung the new alternator supplier and am going to send them a photo of their connection in it and see if I can change it, alternatively take it back to them to do it.

 

Luckily, I have a spare standard alternator that I can fit meantime.

 

"Once the Adverc is working you can persuade it to boost the charging voltage by putting a couple of diodes is series in the sense lead". that sounds like a good idea, I'll get some ready to take.

 

"Trojans like about 14.8 volts so the Adverc should provide this during the high part of its cycle."   that is what I now aspire to, in order to keep my 4 new babies thriving.

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Just checked my Adverc, light comes on with ignition, goes off when engine starts.

Absolutely no need to mess about with diodes, just adjust the Adverc voltage with its voltage adjustment. 4 screws to get into box, one obvious preset in the corner.

 

I suspect the OP has the Adverc voltage set too low. 

 

Adverc has a LOT of components and a protective coating on the board, so resoldering pins not a good idea.

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44 minutes ago, davidb said:

 

When I get back to the boat I shall disconnect this fly lead and measure the voltage on it with engine running through start-up to full voltage, that might tell me which side of the rotor it is connected.

 

The red Adverc sense lead is extended right the way to the battery + terminal.

 

I have rung the new alternator supplier and am going to send them a photo of their connection in it and see if I can change it, alternatively take it back to them to do it.

 

Luckily, I have a spare standard alternator that I can fit meantime.

 

"Once the Adverc is working you can persuade it to boost the charging voltage by putting a couple of diodes is series in the sense lead". that sounds like a good idea, I'll get some ready to take.

 

"Trojans like about 14.8 volts so the Adverc should provide this during the high part of its cycle."   that is what I now aspire to, in order to keep my 4 new babies thriving.

 

Hang on, I am not sure which control side your alternator actually uses. I think the instructions I linked to shows how to tell, I trust following those instructions is what you mean by measuring the voltage on the fly-lead.

 

Where did the Trojans like 14.8 volts come from? At that voltage they will be gassing although the Adverc cycling will minimize it. They certainly like regular equalization. I think regular charging at 14.8 volts will involve you in very regular battery topping up unless you have an automatic watering system.

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11 minutes ago, Tony Brooks said:

 

Hang on, I am not sure which control side your alternator actually uses. I think the instructions I linked to shows how to tell, I trust following those instructions is what you mean by measuring the voltage on the fly-lead.

 

Where did the Trojans like 14.8 volts come from? At that voltage they will be gassing although the Adverc cycling will minimize it. They certainly like regular equalization. I think regular charging at 14.8 volts will involve you in very regular battery topping up unless you have an automatic watering system.

 

The 14.8 comes from the Trojan data sheet, though I have spoken to Trajan about getting them quickly charged in winter on a liveaboard boat and they suggested giving 15volts a go.

I have the Adverc set to 14.8 volts on its higher voltage. I top the batteries up at engine service intervals which is 200 hours.  However in summer when we are doing longish days almost every day I drop down to 14.6 volts.

 

Four of my Trojans are now at the end of their life and use more water, and at the last 200 hour check the tops of the plates were just peeping out at me, but these are 6 years old on a full time off grid liveaboard.

 

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On 29/07/2022 at 18:00, dmr said:

 

The 14.8 comes from the Trojan data sheet, though I have spoken to Trajan about getting them quickly charged in winter on a liveaboard boat and they suggested giving 15volts a go.

I have the Adverc set to 14.8 volts on its higher voltage. I top the batteries up at engine service intervals which is 200 hours.  However in summer when we are doing longish days almost every day I drop down to 14.6 volts.

 

Four of my Trojans are now at the end of their life and use more water, and at the last 200 hour check the tops of the plates were just peeping out at me, but these are 6 years old on a full time off grid liveaboard.

 

 

 

"OK to carefully short that fly-lead to the alternator case with the engine running while watching the battery voltage"

 

I'm back at the boat now and have just done the above with the battery at it's highest voltage - 14.3.  It immediately shot up to 15 or 16 and the adverc lamp started flashing. There seems to be a lot of current going through the green lead so the next time I did it through a 10 watt 12v bulb. The bulb glowed normally and the voltage climbed to 14.45 and now remains there.

 

I have had the back off the adverc and the pot is obvious so now I propose to turn it clockwise a couple of turns then try again with green lead connected?

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42 minutes ago, davidb said:

 

 

"OK to carefully short that fly-lead to the alternator case with the engine running while watching the battery voltage"

 

I'm back at the boat now and have just done the above with the battery at it's highest voltage - 14.3.  It immediately shot up to 15 or 16 and the adverc lamp started flashing. There seems to be a lot of current going through the green lead so the next time I did it through a 10 watt 12v bulb. The bulb glowed normally and the voltage climbed to 14.45 and now remains there.

 

I have had the back off the adverc and the pot is obvious so now I propose to turn it clockwise a couple of turns then try again with green lead connected?

 

The green wire will take the full rotor current of the alternator so a little spark is to be expected.

The Adverc light should not flash, so something is wrong but I don't know what fault conditions the Adverc detects.

The voltage is too high 😀

Its possible that the Adverc voltage is set much too high but this is unlikely, more likely the Adverc has got a fault or one of the other wires is not connected correctly.

I think the red wire to the battery might be the one to check first ?????

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Sorry, I only speed read your post as I was doing other boaty stuff.

Im not exactly sure why you are shorting the alternator flying lead to ground, is this to confirm that it is correctly wired to the correct place inside the alternator? if so your tests do suggest that its correct.  

With the engine running can you slowly turn the Adverc pot and observe the measured voltage....at some point it should start to increase.

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2 hours ago, dmr said:

s this to confirm that it is correctly wired to the correct place inside the alternator

Yes, and I won't make a habit of it.

 

Will try the pot adjustment tomorrow, thanks.

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I have checked again where the red adverc wire goes and it is to the  domestic isolator switch right next to the battery.

 

I'm afraid turning the pot seems to make no difference i.e. 6 turns clockwise then back. 12 x anti clock then back. And the voltage remains at about 14.3.

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It looks like the Adverc is not working and so the 14.3 is the voltage of the internal regulator.

Tell me again.....does the Adverc light come on when you turn the ignition on, and go off when the engine starts?

 

I believe the Adverc is pretty reliable so double check all the wiring and connections.

 

Its my opinion (based on real experience) that the Adverc is essential for charging Trojans, at least on a liveaboard boat.

Note that there are several on eBay right now and one is £20 or best offer 😀

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I’ve just had an odd fault with my Adverc which I do need to write up fully and post on here…but in short the Thermistor in the red wire went into fault and caused all sorts of odd behaviour despite checking out ok when the resistance was measured on the white cables. One of the faults was that the adverc didn’t regulate at the higher voltage. It might be worth checking. New ones are available from adverc or CPC/RS/eBay etc. You will need to be able to solder if you just get the component…adverc supply with fly leads so you can crimp it in. 

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12 minutes ago, frangar said:

I’ve just had an odd fault with my Adverc which I do need to write up fully and post on here…but in short the Thermistor in the red wire went into fault and caused all sorts of odd behaviour despite checking out ok when the resistance was measured on the white cables. One of the faults was that the adverc didn’t regulate at the higher voltage. It might be worth checking. New ones are available from adverc or CPC/RS/eBay etc. You will need to be able to solder if you just get the component…adverc supply with fly leads so you can crimp it in. 

 

The Adverc is an old design and low technology, all done with discrete chips, so its self diagnostics are very limited. Alternatives like the Sterling are processor based and much better at spotting faults, but I think the Adverc is still significantly better at the core job of alternator control. It would be good if Adverc would update their design....but they won't.

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1 hour ago, dmr said:

It looks like the Adverc is not working

It is beginning to look like that. I have another of the same model on another sea boat, so I will see what that does at weekend when we launch it, and then try swapping them over. At least they are made in Wolverhampton, and are repairable.

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Just now, dmr said:

 

The Adverc is an old design and low technology, all done with discrete chips, so its self diagnostics are very limited. Alternatives like the Sterling are processor based and much better at spotting faults, but I think the Adverc is still significantly better at the core job of alternator control. It would be good if Adverc would update their design....but they won't.

I love my adverc! It’s now 25 years old and got a clean bill of health from them when I sent it back trying to find the fault this time…don’t get me started on the Sterling light show….or their build quality…I think the thermistor had failed due to age and exposure to acid fumes over the years lying on the battery bank. 
 

I suppose some updating would be good as alternators become more controlled by a vehicles ECU rather than working stand alone….but sometimes simple & effective is best. 

2 minutes ago, davidb said:

It is beginning to look like that. I have another of the same model on another sea boat, so I will see what that does at weekend when we launch it, and then try swapping them over. At least they are made in Wolverhampton, and are repairable.

Have you checked the brushes on the Alternator?? I had quite a bit of wear on the one the adverc was connected to on my A127….whilst it wasn’t the fault it was soon going to introduce one as it had reached the end of its travel.  

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10 minutes ago, frangar said:
12 minutes ago, davidb said:

Have you checked the brushes on the Alternator?

It was new less than 12 months ago. I have just bought the top one off eBay thanks for all your help I'll report back when I have tried it.

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3 minutes ago, davidb said:

It was new less than 12 months ago. 

 

Fault tracing is all about testing stuff and proving it works, then ruling it out as a possible cause.

 

There is something busted that shouldn't be, and assuming that something (e.g. the brushes) must be working correctly because the alternator is less than a year old is to leave something unknown. 

 

I suggest checking those brushes regardless, if only to rule them out. You "could" otherwise expend a whole load of time and effort looking elsewhere for the fault then in desperation, finally check the brushes and find them goosed. You've already set out along this path by buying another Adverc. What if that too behaves the same when you fit it?

 

 

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