More Charging problems

[David Schweizer]

You may recall me reporting last year that the charging system on our boat was suffering from intermittent problems, and a number of useful suggestions were made by several people with far more knowledge in these matters than myself. I was geared up to try out the variouis solutions when the problem ceased occuring, so I left well alone and all has been well during a summer of extensive cruising.. Well it has started up again.

 

I will start by describing the charging regime on our boat and then reiterate the problem, The system comprises a 55amp Lucas A127 Alternator on a 3 to 1 pulley ratio, a Sterling Digital Advanced Alternator Regulator, a Durite 180 amp split charge relay (yes I know!!), two 6volt 240amp US Battery Corp extra deep cycle domestic batteries (in series), and a Standard 643 lorry type starter battery.

 

The problem has been, and once again is, that on occassions, the Alternator will not kick in and deliver any charge, in the past removing the wire between the Alternator D+ terminal and the charge warning light and then replacing it has usually cured the fault, although it sometimes took several attempts. Afew weeks ago this solution refused to work, so remembering earlier advice, I robbed the Regulator/brush set from a spare alternator and fitted it to the alternator on the engine, and it worked, so i was convinced that was where the problem must have lain.

 

The problem recurred again last week and although I was doubtful that the regulator would have failed so quickly, I replaced it again with another new one, my doubts were confirmed as the Alternator still refused to deliver any charge, however this time I noticed that the Domestics charge ammeter whacked right across to discharge when I attempted to start the engine, even though the Start battery was showing a healthy voltage on the voltmeter. This suggested that there must be a short in the system so I conducted a number of tests. I discovered that there was a contuinuity between the two battery terminals on the Relay, even when everything was switched off. Having concluded that the relay contacts must have welded themselves together, I decided that I needed to invest in one of the Curtis Albright Solenoids that Chris Gibson recommends, however it still does not explain why the Alternator would not kick in.

 

Having almost resigned myself to leaving the boat with a partially discharged Domestic bank, I just gave it one more try, and the ammeter behaved normally, the engine started and the alternator showed a healthy charge. I am still going to invest in one of the Albright switches, but am at a loss as to why this problem occurs several times, and then does not recurr for months. Is it the relay or something else? should I also replace the alternator ( I have two spares plus a couple of spare Regulators. Or (dare I say it) is it the Sterling Alternator Regulator?

 

Any advice would be gratefully received.

Edited September 6, 2009 by David Schweizer

[OldGoldy]

You may recall me reporting last year that the charging system on our boat was suffering from intermittent problems, and a number of useful suggestions were made by several people with far more knowledge in these matters than myself. I was geared up to try out the variouis solutions when the problem ceased occuring, so I left well alone and all has been well during a summer of extensive cruising.. Well it has started up again.

 

I will start by describing the charging regime on our boat and then reiterate the problem, The system comprises a 55amp Lucas A127 Alternator on a 3 to 1 pulley ratio, a Sterling Digital Advanced Alternator Regulator, a Durite 180 amp split charge relay (yes I know!!), two 6volt 240amp US Battery Corp extra deep cycle domestic batteries (in series), and a Standard 643 lorry type starter battery.

 

The problem has been, and once again is, that on occassions, the Alternator will not kick in and deliver any charge, in the past removing the wire between the Alternator D+ terminal and the charge warning light and then replacing it has usually cured the fault, although it sometimes took several attempts. Afew weeks ago this solution refused to work, so remembering earlier advice, I robbed the Regulator/brush set from a spare alternator and fitted it to the alternator on the engine, and it worked, so i was convinced that was where the problem must have lain.

 

The problem recurred again last week and although I was doubtful that the regulator would have failed so quickly, I replaced it again with another new one, my doubts were confirmed as the Alternator still refused to deliver any charge, however this time I noticed that the Domestics charge ammeter whacked right across to discharge when I attempted to start the engine, even though the Start battery was showing a healthy voltage on the voltmeter. This suggested that there must be a short in the system so I conducted a number of tests. I discovered that there was a contuinuity between the two battery terminals on the Relay, even when everything was switched off. Having concluded that the relay contacts must have welded themselves together, I decided that I needed to invest in one of the Curtis Albright Solenoids that Chris Gibson recommends, however it still does not explain why the Alternator would not kick in.

 

Having almost resigned myself to leaving the boat with a partially discharged Domestic bank, I just gave it one more try, and the ammeter behaved normally, the engine started and the alternator showed a healthy charge. I am still going to invest in one of the Albright switches, but am at a loss as to why this problem occurs several times, and then does not recurr for months. Is it the relay or something else? should I also replace the alternator ( I have two spares plus a couple of spare Regulators. Or (dare I say it) is it the Sterling Alternator Regulator?

 

Any advice would be gratefully received.

 

I once helped one of my club colleagues out with a similar problem. The battery and charge arrangements were as basic as they could be. I traced & marked every wire so that I could understand what was in place. Eventually, I got a manual from Deutz. Everything was wired correctly, but untidily. In the end, I found that the charge warning lamp was not of the correct rating. (The control panel was not from Deutz) It wasn't open-circuited and lit up OK when presented with 12volts directly. The bulb was changed and, hey presto we now had enough current to excite the alternator windings! - Job done - It may pay you to look anlong these lines before you start tearing your hair out 8^)

[Gibbo]

Intermittent open circuit on the rotor of the alternator or dirty slip rings.

 

When you switch on the ignition, the charge warning light feeds a current into the D+ terminal, the regulator (trying the get the D+ terminal up to about 14 volts or so - afterall it doesn't know the alternator isn't spinning yet) will pass all this current through the rotor which magnetises the rotor. In doing so, it tries to pull far more current than the charge warning light can deliver and thus pulls the D+ terminal down to 1 or 2 volts or something round there. As soon as the engine fires, the alternator picks itself by its own boot laces producing an increasing voltage at the D+ terminal, which consequently passes more current through the rotor, which gives a stronger magnetic field until the output is maximum. All this happens extremely quickly. The D+ terminal goes up to 14 volts or so and the split charge relay energises.

 

If the rotor circuit goes open circuit (slip rings or rotor windings), when you switch on the ignition, the charge warning light passes that same current to the D+ terminal just as normal but there is no rotor to "eat" the current so the D+ terminal goes right up to battery voltage. That will be enough (assuming a normal size charge warning light) to energise a Durite split charge relay so as soon as you try to start the engine some of the starter current will come from the domestic bank via the split charge relay.

 

This is all assuming that the relay is indeed energised from the D+ terminal.

 

Gibbo

[BEngo]

You may recall me reporting last year that the charging system on our boat was suffering from intermittent problems, and a number of useful suggestions were made by several people with far more knowledge in these matters than myself. I was geared up to try out the variouis solutions when the problem ceased occuring, so I left well alone and all has been well during a summer of extensive cruising.. Well it has started up again.

 

I will start by describing the charging regime on our boat and then reiterate the problem, The system comprises a 55amp Lucas A127 Alternator on a 3 to 1 pulley ratio, a Sterling Digital Advanced Alternator Regulator, a Durite 180 amp split charge relay (yes I know!!), two 6volt 240amp US Battery Corp extra deep cycle domestic batteries (in series), and a Standard 643 lorry type starter battery.

 

The problem has been, and once again is, that on occassions, the Alternator will not kick in and deliver any charge, in the past removing the wire between the Alternator D+ terminal and the charge warning light and then replacing it has usually cured the fault, although it sometimes took several attempts. Afew weeks ago this solution refused to work, so remembering earlier advice, I robbed the Regulator/brush set from a spare alternator and fitted it to the alternator on the engine, and it worked, so i was convinced that was where the problem must have lain.

 

The problem recurred again last week and although I was doubtful that the regulator would have failed so quickly, I replaced it again with another new one, my doubts were confirmed as the Alternator still refused to deliver any charge, however this time I noticed that the Domestics charge ammeter whacked right across to discharge when I attempted to start the engine, even though the Start battery was showing a healthy voltage on the voltmeter. This suggested that there must be a short in the system so I conducted a number of tests. I discovered that there was a contuinuity between the two battery terminals on the Relay, even when everything was switched off. Having concluded that the relay contacts must have welded themselves together, I decided that I needed to invest in one of the Curtis Albright Solenoids that Chris Gibson recommends, however it still does not explain why the Alternator would not kick in.

 

Having almost resigned myself to leaving the boat with a partially discharged Domestic bank, I just gave it one more try, and the ammeter behaved normally, the engine started and the alternator showed a healthy charge. I am still going to invest in one of the Albright switches, but am at a loss as to why this problem occurs several times, and then does not recurr for months. Is it the relay or something else? should I also replace the alternator ( I have two spares plus a couple of spare Regulators. Or (dare I say it) is it the Sterling Alternator Regulator?

 

Any advice would be gratefully received.

 

Have a look at the slip rings. If it is a typical Lucas Alternator then the brushes eventually wear a hole in the centre slip ring. Sometimes this contacts the brush well enough for a field current, sometimes it doesn't.

 

N

[James T Berk]

Have a look at the slip rings. If it is a typical Lucas Alternator then the brushes eventually wear a hole in the centre slip ring. Sometimes this contacts the brush well enough for a field current, sometimes it doesn't.

 

N

They don't make 'em like that any more. The A127 has conventional axial slip rings.

See I'm managing aren't I so long as I've got my boys own book of facts.

Edited September 6, 2009 by James T Berk

[David Schweizer]

It would appear from the above comments, that the fault may well be in the Alternator, which I shall replace when I next visit the boat. However, I am a bit miffed as the Alternator was brand new three years ago and has only been run for about 700 hours, the previous one lasted over eight years, and then only failed becaue oil got into it from the blown engine.

 

Is it normal for an alternartor to fail after such a short period of time?

[Gibbo]

It would appear from the above comments, that the fault may well be in the Alternator, which I shall replace when I next visit the boat. However, I am a bit miffed as the Alternator was brand new three years ago and has only been run for about 700 hours, the previous one lasted over eight years, and then only failed becaue oil got into it from the blown engine.

 

Is it normal for an alternartor to fail after such a short period of time?

 

Don't confuse "wearing out" with "breaking".

 

Anything, at any age, can break. Sometimes after 30 seconds of use. Some equipment doesn't work at all straight out of the box.

 

Gibbo

[WotEver]

Some equipment doesn't work at all straight out of the box.

 

In those cases it usually has "Made In China" written somewhere on the outside...

 

T

[paulcatchpole]

Don't confuse "wearing out" with "breaking".

 

Anything, at any age, can break. Sometimes after 30 seconds of use. Some equipment doesn't work at all straight out of the box.

 

Gibbo

 

Surely even more likely in the first 30 seconds of use?

 

If things survive that, then they'll probably work for a while at least, seems to be the case with electronic kit, IMO.

 

You're bang on, on the latter part as well - when I used to build PCs (hateful, pointless business concept), before getting a proper job, we were getting up to 6% (by volume) of kit DOA from a particular supplier.

 

PC

[WotEver]

when I used to build PCs

 

Me too.

 

(hateful, pointless business concept

 

It was, yes.

 

T

[Gibbo]

Surely even more likely in the first 30 seconds of use?

 

If things survive that, then they'll probably work for a while at least, seems to be the case with electronic kit, IMO.

 

Indeed. It's called the bathtub curve and applies very well to electronics. 45% of failures in the first 60 days, then just under 7 years of almost trouble free operation (10% of failures), then they start to break with monotonous regularity. Whether it's switched on or off makes no difference to this!

 

Of course this assumes that it's designed properly in the first place.

 

Gibbo

 

....................when I used to build PCs (hateful, pointless business concept), before getting a proper job, we were getting up to 6% (by volume) of kit DOA from a particular supplier.

 

That sounds very much like they were shipping them untested. 6% is about the expected failure rate of brand new PCBs direct from PCB assembler. The designer/manufacturer then run the tests and (usually) repair those 6% in house. If the failure rate goes above 6% they get sent back to the PCB assembler. That's more or less the accepted practice. If you were getting 6% failure as an end customer there was something horribly wrong somewhere.

 

Gibbo

[Sir Nibble]

It would appear from the above comments, that the fault may well be in the Alternator, which I shall replace when I next visit the boat. However, I am a bit miffed as the Alternator was brand new three years ago and has only been run for about 700 hours, the previous one lasted over eight years, and then only failed becaue oil got into it from the blown engine.

 

Is it normal for an alternartor to fail after such a short period of time?

Sure that no oil has got into the replacement? Oddly, oil contamination wears out the slip ring in double quick time and produces a cotton wool like conductive fluff all around the brush area.

[David Schweizer]

Sure that no oil has got into the replacement? Oddly, oil contamination wears out the slip ring in double quick time and produces a cotton wool like conductive fluff all around the brush area.

No the engine has been completely re-built and there are no leaks or oily fumes in the engine box, in fact the Alternator still looks brand new, The brushes on the old regulator looked perfect as did the slip ring (I assume that is what we used to call the commutator - Copper segments around the shaft that the brushes run against?)

[Sir Nibble]

No the engine has been completely re-built and there are no leaks or oily fumes in the engine box, in fact the Alternator still looks brand new, The brushes on the old regulator looked perfect as did the slip ring (I assume that is what we used to call the commutator - Copper segments around the shaft that the brushes run against?)

Commutator is a different device made up of segments, the slip rings are continuous rings unsegmented, but yes, that's the bunny.

[David Schweizer]

Well the Albright SW180B-2 solenoid arrived yesterday, and I can now understand why Gibbo referred to the Durite relay on on my boat at the meoment as a bit "Girlie". The Albright is large and very heavy. and the contacts are massive by comparison. A very impressive piece of equipment.

 

I have downloaded the technical info from The Curtis-Albright site, but am still uncertain whether the coil connection spade terminals are polarity sensitive. There are no markings on the casing so I am assuming that they can be connected either way round, however advice would be welcome. I am also assuming that the spade terminals opposite each other are connected and that one can use the pair on either side.

 

Still got to sort out the alternator though. I think i will replace it just in case and have the other one checked out.

[OldGoldy]

Well the Albright SW180B-2 solenoid arrived yesterday, and I can now understand why Gibbo referred to the Durite relay on on my boat at the meoment as a bit "Girlie". The Albright is large and very heavy. and the contacts are massive by comparison. A very impressive piece of equipment.

 

I have downloaded the technical info from The Curtis-Albright site, but am still uncertain whether the coil connection spade terminals are polarity sensitive. There are no markings on the casing so I am assuming that they can be connected either way round, however advice would be welcome. I am also assuming that the spade terminals opposite each other are connected and that one can use the pair on either side.

 

Still got to sort out the alternator though. I think i will replace it just in case and have the other one checked out.

 

Did you try changing the warning light bulb for one with a different (higher) rating, ie more current?

[David Schweizer]

Did you try changing the warning light bulb for one with a different (higher) rating, ie more current?

No not yet. I am going to wait and see if the new solenoid (relay) continues to energize as soon as I turn the (Ignition) key on. If it does I already have a Resistor recommended by ChrisW which can be soldeered across the lamp terminals to rectify the problem.

 

Thanks for the continued interest, I will keep you all informed.

[wonderdust]

No not yet. I am going to wait and see if the new solenoid (relay) continues to energize as soon as I turn the (Ignition) key on. If it does I already have a Resistor recommended by ChrisW which can be soldeered across the lamp terminals to rectify the problem.

 

Thanks for the continued interest, I will keep you all informed.

 

 

Is your relay energized by 12v from the ignition switch or the D+ on the alternator?

Edited September 12, 2009 by wonderdust

[David Schweizer]

Is your relay energized by 12v from the ignition switch or the D+ on the alternator?

 

From the D+ on th alternator, but of course that also acts as the negative earth for the charge indication light, so if power passes through the lamp, it energizes the relay. I am assured that the new relay will n ot be energized by the small cuurent, but time will tell.

 

But tht is only one of my problems, the main one is that the Alternator intermitently fails to kick in and charge. I have read that one can energize the Relay via the B+, but as that is directkly connected to the Domestic battery, I cannot see how the relay will not be enegized all the time.

Edited September 12, 2009 by David Schweizer

[Gibbo]

Well the Albright SW180B-2 solenoid arrived yesterday, and I can now understand why Gibbo referred to the Durite relay on on my boat at the meoment as a bit "Girlie". The Albright is large and very heavy. and the contacts are massive by comparison. A very impressive piece of equipment.

 

I have downloaded the technical info from The Curtis-Albright site, but am still uncertain whether the coil connection spade terminals are polarity sensitive.

 

No they're not polarity sensitive.

 

There are no markings on the casing so I am assuming that they can be connected either way round, however advice would be welcome. I am also assuming that the spade terminals opposite each other are connected and that one can use the pair on either side.

 

Correct.

 

Gibbo

 

But tht is only one of my problems, the main one is that the Alternator intermitently fails to kick in and charge. I have read that one can energize the Relay via the B+, but as that is directkly connected to the Domestic battery, I cannot see how the relay will not be enegized all the time.

 

You're correct in your reasoning. It would indeed be energised all the time.

 

Gibbo

[Sir Nibble]

But tht is only one of my problems, the main one is that the Alternator intermitently fails to kick in and charge. I have read that one can energize the Relay via the B+, but as that is directkly connected to the Domestic battery, I cannot see how the relay will not be enegized all the time.

I suspect David, that what you have been told about energising the relay from B+ may in fact be an effort to "flash" the alternator.

Intermittant A127 alternators.

Remove the regulator. Where the metalwork of the brush holder meets the metalwork of the actual regulator circuit, there is a spot welded joint. Inspect carefully. Also, where the regulator mounts, the screwhole that stands proud on a boss, that's the earth connection, see it's clean and tight.

The rotor windings are crimped to the slip ring "legs" and sometimes the crimping is over enthusiastic and almost severs the wire which eventually breaks. You can test them with a little tweak and access them one at a time through the hole left by the regulator by turning the rotor.

[WotEver]

removed because I'd missed the fact that what I had to say had already been said

Edited September 13, 2009 by WotEver

[pistnbroke]

Alternator Life Span

 

The design life of a vehicle is 5000 hours so ask yourself how many alternators would you change in a vehicles life ? The only parts that wear are the brushes/slip rings and bearings .....though many of the regulators tend to degrade in terms of the setting of the voltage regulator ..... Of course the old lucas equipment was designed to last the warantee period ie 12 months

 

Hope you like the new Avatar ...no beard on this one ...and its not what you think

Edited September 13, 2009 by pistnbroke

[Justme]

5000 hours?

 

Thats only 2 hours per day for 6.5 years. Most cars last longer than that.

 

Or

 

5000 hours at an average of 45mph = 225000miles most cars do that & more now days.

 

225000 miles at 8k per year is 28 years.

 

Yeh I guess going on mph & miles covered 5000 hours is about right.

[David Schweizer]

No they're not polarity sensitive.

 

Correct.

 

Gibbo

 

You're correct in your reasoning. It would indeed be energised all the time.

 

Gibbo

Thanks for the replies, That is very helpful. At least I should be able to fit the new solenoid without too much problem, except that the terminal rings fitted on the cables are 6mm, and the studs on the Albright are 8mm. I have some spare 8mm ones on the boat, but from memory they are the same size as the 6mm but with bigger holes, I will try drilling them out first rather than mess about changing them.

 

 

 

I suspect David, that what you have been told about energising the relay from B+ may in fact be an effort to "flash" the alternator.

Intermittant A127 alternators.

Remove the regulator. Where the metalwork of the brush holder meets the metalwork of the actual regulator circuit, there is a spot welded joint. Inspect carefully. Also, where the regulator mounts, the screwhole that stands proud on a boss, that's the earth connection, see it's clean and tight.

The rotor windings are crimped to the slip ring "legs" and sometimes the crimping is over enthusiastic and almost severs the wire which eventually breaks. You can test them with a little tweak and access them one at a time through the hole left by the regulator by turning the rotor.

Well I think I understand all that, but to inspect the seatings, I will have to remove the Alternator anyway. I could always bring it back home with me and try and persuade you to have a llok at it when you are at Hilperton some time.

Edited September 13, 2009 by David Schweizer