Alternator Problem? Assistance needed

[acdbox]

Ok. Thanks for being patient with me while I did some testing.

The results are I think I've isolated a problem with the alternator.

After a few prior tests kept brining up the same issue I decided to install the sterling regulator to see of that could resolve matters and in doing so have found the problem the alternator.

There seems to be a connection being made somewhere that shouldn't.

I believe it is possibly the regulator when it is inserted into the alternator but am unsure.

 

Would this make any sense as to cause the original problems I was experienceing?

 

Thank you

Andreas

Oh, the alternator was corrected in it's wiring, apologies i never responded on previous thread to say so.

The shunt has been wired correct as per the instructions, double and triple checked.

[WotEver]

Yes it makes sense that there was faulty wiring to/around the alternator. This will have probably killed the battery.

 

If you believe that there is now no load on the battery with everything switched off and you believe that the charging circuit is working as it should then put a new battery in and report back your findings

[acdbox]

Hi WotEver,

The battery probably has had it without a proper charge, though before I put a new bat in id like to resolve the alternator issue to prevent it happening again.

I may not have been clear in previous post, apologies.

The alternator has a connection problem... When a continuity test is put between the new connection made to the alternators regulator and the alternators casing it's showing there's a connection, as I understand it there shouldn't be a connection there. I've double/triple checked the new connection is not touching the casing in any way but it still shows a connection.

 

Hope that makes a bit better sense?

[Paul C]

That's good to hear, but it does sound like the original alternator issue killed the battery(ies), from which full health is unlikely to be restored.

[nicknorman]

Hi WotEver,

The battery probably has had it without a proper charge, though before I put a new bat in id like to resolve the alternator issue to prevent it happening again.

I may not have been clear in previous post, apologies.

The alternator has a connection problem... When a continuity test is put between the new connection made to the alternators regulator and the alternators casing it's showing there's a connection, as I understand it there shouldn't be a connection there. I've double/triple checked the new connection is not touching the casing in any way but it still shows a connection.

Hope that makes a bit better sense?

It depends what you mean by "a connection". I think I am right in saying that the external regulator will connect to the rotor (field coil) and via that, to -ve which is also the case. The resistance of the field coil is just a few ohms (maybe 3 or 4) and so a continuity tester may well show a circuit to the case but this isn't a fault.

 

I suggest checking carefully with the meter set to the lowest ohms range. Firstly hold the probes together to check the zero reading, then put it across the suspect connection and measure the ohms, that being the difference between that reading and the reading you got when you held the probes together.

Edited February 13, 2016 by nicknorman

[Tony Brooks]

I am not clear as to where you are connecting the meter on the alternator. I think its a normal A127 and if so the regulator is likely to allow current to pass when the alternator is stationary. Otherwise the warning lamp would not come on when you turn the ignition on. The warning lamp runs to "earth" (negative) via the regulator.

 

I also am not clear a to what "the new connection made to the regulator" is. If this is the extra one an external regulator requires then are you sure it has been attached to the correct brush? The external regulator shorts out the internal one so if the inbuilt regulator is in the positive side of the rotor that new wire will show continuity to earth - I was about to give the resistance figure of the rotor but Nick beet me to it.

[acdbox]

Hi nicknorman/tony,

Hmmm. Yes the new connection is to field on the alternator, and that makes sense what you say about it connecting to the -ve. Just the instructions I was following specifically state there should be no continuity with the case...

Just checked again the multimeter Shows a difference from 137.6 to 18 when connected.

[Arthur Brown]

If there is/was a standing discharge measurable in amps then no amount of fussing over the odd point of a volt of charge voltage will solve anything, no charger even with a battery boiler will keep flat batteries healthy.

 

First a total clean is a help -so it's a pleasure to work there, then a good diagram of the ACTUAL wiring. Then compare the actual with the desired wiring and make changes.

My past experience is that no-one is an expert on ALL the systems in a boat so get Sir Nibble to design your complete charging system and fit it as he says -even pay him as a job to do it for you.

 

Remember that if left flat the life of a lead acid (any type) battery is measured in weeks so a flat battery that's been flat for six months is not a battery it's ballast.

 

Without getting the generation sorted out you need to get a mooring with a permanent shoreline.

[nicknorman]

Hi nicknorman/tony,

Hmmm. Yes the new connection is to field on the alternator, and that makes sense what you say about it connecting to the -ve. Just the instructions I was following specifically state there should be no continuity with the case...

Just checked again the multimeter Shows a difference from 137.6 to 18 when connected.

Again, I think it depends what is meant by continuity. I suspect it means a dead short circuit, which would of course be wrong. I'm not quite sure what the figures you quote are, but what does the meter on ohms range show when you put it between the connection and the case?

[acdbox]

Hay Arthur,

I'm far from an expert, actually more towards the newbie. Would be nice to have external design/installation though honestly don't have the finances to be able to achieve that at the moment.

The comments so far on this thread have been the most helpful yet and have been ruling out possible causes one by one.

If as Nick says there should actually be a connection between the field and the case then that should all but pass the alternator and a battery test is next.

Thanks

[Arthur Brown]

BOAT -Bring Out Another Thousand. If you don't afford to get the charging system right then you need to call it a small flat and get mains installed. Or you could buy new batteries monthly and regard them as primary cells.

[Tony Brooks]

I was about to say the same thing as Nick. If we are all talking about the same thing then my comment would be that the figures look too high for Ohms and too low for diode test readings.

 

I also do not understand what you mean by "Shows a difference from 137.6 to 18 when connected."

 

I think there is something about your test procedures that you assume we know. I have had a telling off before for suggesting that a questioner did not know what they were doing and should thus get professional help. It may well be me but I find what you are trying to tell us difficult to understand.

 

Is the battery in your meter in good order. If it is getting flat the meters will often give very odd readings.

Edited February 13, 2016 by Tony Brooks

[acdbox]

Hi,

Ok yes arthur what you say is true.

 

Tony, apologies I'm still new to this and am attempting to learn as I go. I haven't learnt enough with regards to resistance testing and have been going on a obviously wrong judgment that 0 or change in reading means a connection.

 

When I set it to test continuity it shows a reading around .113 and will go up to .16 when connected through the alternator.

Hadn't thought to check the multimeters batteries.

 

I did get someone in to have a look over things but obviously I scared him off as he has been all but impossible to get back.

 

I thought with a little bit of willingness and a relatively simple setup at the moment I could achieve some of the tasks at hand? And ofcourse I'd have to be able ask you all for a bit of direction too.

Understand that maybe a little rude to rely on this forum and I apologise for that.

[nicknorman]

Not it isn't rude, however it can be frustrating for those trying to help! So when you say .113 and .16 it doesn't mean anything unless you tell us what the units are and what range / setting you have the meter on. You mention "continuity" again but best to set it to an ohms range (the lowest one) so that the meter is reading ohms. It may be a symbolic representation for ohms in which case look up the Greek letter omega (capital) and see if there is that symbol on the range selector knob.

[Tony Brooks]

No need to apologise but please bear in mind that we do not know exactly what you have done.

 

Normally the continuity tester on a multi-meter just sounds a buzzer if you have continuity, any reading may or may not be meaningless.

 

When the meter is set to the Ohms scale (a sort of upper-case O with two little feet is the symbol) the meter will read 1 but actually it is a capital i because it is on the "wrong" side of the display. You then should firmly touch the meter leads/probes together and the meter should read 0 (zero) but on the 200 Ohm scale they often read about 0.2 to 0.3 of an ohm. This should be subtracted for the final reading but for what you are doing just ignore it. For all 12/24V work use the 200 ohm scale. Just get good clean and firm connections to where ever you are measuring and then just read the number. If it gradually rises you may be dealing with a capacitor.

 

For all intents and purposes and in this case we can consider both your readings to be Zero and zero does indicate a good connection.

 

On Ohms you normally get a steady reading and in the case of the extra lead to case/negative I would expect it to be the 3 to 4 Ohms Nick mentioned.

 

Have another look at the instructions. I would expect them to have two slightly different sets of readings depending upon whether the regulator is in the positive or negative side of the rotor.

 

Who fitted the extra wire to the brush holder? Are you sure its on the correct side?

 

I think Nick and myself are saying the same thing.

 

If you go onto my website and look in the Electrical Course Notes there is a section on setting and using multi-meters

Edited February 13, 2016 by Tony Brooks

[MtB]

And just to clarify a basic no-one has clearly explained, an Ohm is the unit of resistance.

 

The higher the resistance in a circuit, the higher the number of Ohms your meter will display. The higher the resistance of a circuit, the lower the electrical current will be, for a given Voltage. The current is measured in Amps. The Voltage is the amount of electrical 'pressure' causing the current, and is measured in Volts.

 

The voltage can be considered analogous (roughly) to the water pressure in a tap. And the current analogous to the rate of flow from the tap when turned ON. The degree to which the tap is turned ON can be considered roughly equivalent to the 'resistance'.

[WotEver]

And a capacitor is a bucket...

 

 

And a battery is a much, much bigger bucket.

[MtB]

I'd say the battery is not so much a bucket (like a capacitor, i.e. filled from the tap), but more like the municipal water tower on the top of that hill five miles away, feeding the water to the tap...

 

[WotEver]

And the alternator is the dark clouds in the sky above the water tower...

[David Mack]

A capacitor is more like the accumulator in your boat's domestic water system.

 

And if you are refilling the municipal water tower it takes barely any longer to fill the last 6" than it does to fill the first 6".

[MtB]

As I said, these are rough anologies. They don't stand up to detailed scrutiny.

[Tony Brooks]

And just to clarify a basic no-one has clearly explained, an Ohm is the unit of resistance.

 

The higher the resistance in a circuit, the higher the number of Ohms your meter will display. The higher the resistance of a circuit, the lower the electrical current will be, for a given Voltage. The current is measured in Amps. The Voltage is the amount of electrical 'pressure' causing the current, and is measured in Volts.

 

The voltage can be considered analogous (roughly) to the water pressure in a tap. And the current analogous to the rate of flow from the tap when turned ON. The degree to which the tap is turned ON can be considered roughly equivalent to the 'resistance'.

 

 

Always remembering that when the thing appears to read 1 (one) it probably does not. It is reading I for Infinity and that really means "the resistance here is too high to measure on this setting".

[WotEver]

And if you are refilling the municipal water tower it takes barely any longer to fill the last 6" than it does to fill the first 6".

Imagine it's like a balloon, and as it fills it sags and makes the opening smalle and smaller...

 

Okay, maybe not

[nicknorman]

Imagine it's like me at the Indian restaurant. I gobble the first mouthfuls down really fast, but then I start to get bloated and the final soupçon of rice takes me ages to finish.

[acdbox]

Hi, no the analogies have been good, helpful to me understanding.

Attempting to put it on the ohms setting and then change the range accordingly to the lowest setting.

It basically has two option one with a k and one with an M. Then a further three options for where the decimal is placed within the screen.

On the M option and the decimal set to read thousands (which I guess is milli ohms and thousands being the smallest reading possible?) it displays 0 and doesn't change when wires are touched.

It has an auto option which displays 137.6 on screen not i or 1 like stated. When testing the alternator this goes down to 18.

Deffinetly the ohm setting