Possible Charging Problem

[john6767]

Sorry about this, another electrical/charging thread.

Set up is a Beta 35 with 2 alternators, the domestic one (75A I think) having some form of Beta charge controller on it.  There are 2 x 135 Ah domestic batteries which are about 2.5 years old.

My concern is that the voltage when the batteries are “fully charged” and the engine is running is 14.8V, measured with the Smartguage.

I took some measurements back in Nov (I only remembered to get the piece of paper from the boat today).

Fri evening having left the marina and about an hour away I noticed that there were 5 or so quick flashes of the domestic alternator light.  It was half-light so perhaps this has happened before and I have not seen it as the light is not very bright.  The voltage was 14.8V and the Smartguage showed 100% (it had been on shoreline charge for a couple of weeks at least).  I wondered if the controller was trying to tell me something with the flashes, but the only thing a search pulled up is this thread

https://canalworld.net/forums/index.php?/topic/12952-battery-charge-light-flickering-why/

although that talks about flickering light, and I would say what I saw was a specific set of flashes.

The following morning the voltage was 12.4V and the Smartguage showed 76%, which was to be expected.  With the engine running the voltage was 14.4V and with a clamp meter on the alternator output, at 1000rpm it was outputting 70A, and at 1500rpm 75A.

At lunch time after the engine had run for 4 hours the Smartgruage showed 100% and the voltage 14.8V with the engine running.

So the thing that to me seems strange is the 14.8V when the batteries are “fully charged” and the engine is running, is that correct or is it indicating a fault with the alternator?
 

Edited February 6, 2018 by john6767
clarify that the 14.8V is with the engine running

[Nickhlx]

We have the Beta 43 which has an Iskra 175Amp domestic alternator, with Trojan wet batteries, and this is set to 14.8 volts so I guess its a chosen voltage by Beta for their alternator suppliers to configure. I think it is because it is high enough to not need frequent equalisation charges, and gives relatively quicker charge times for those who maybe don't cruise 24/7 (like us)...  The boat is now in its 9th year and still on the first set of batteries, although ready to replace this year...

 

[WotEver]

11 minutes ago, john6767 said:

So the thing that to me seems strange is the 14.8V when the batteries are “fully charged”, is that correct or is it indicating a fault with the alternator?

Neither. The charging voltage won’t tell you when the batts are fully charged and neither will the SmartGauge (that info is buried in the manual somewhere). The only simple way of accurately ascertaining 100% charge (or nearasdammit) is by measuring the charging current at your 14.8V charge voltage.

(Or taking specific gravity readings of the electrolyte, but that’s not ‘simple’.)

No idea about the flickering lights. That sounds like a bad connection somewhere. First suspect is the isolator, especially if it’s one of those with the removable red keys. 

[bizzard]

Flickering lights before the eyes could mean a migraine's coming on.

[WotEver]

6 minutes ago, bizzard said:

Flickering lights before the eyes could mean a migraine's coming on.

Or in my mate’s case, high blood pressure. 

[bizzard]

1 minute ago, WotEver said:

Or in my mate’s case, high blood pressure. 

Yes, too much salt probably.

[john6767]

17 minutes ago, WotEver said:

Neither. The charging voltage won’t tell you when the batts are fully charged and neither will the SmartGauge (that info is buried in the manual somewhere). The only simple way of accurately ascertaining 100% charge (or nearasdammit) is by measuring the charging current at your 14.8V charge voltage.

(Or taking specific gravity readings of the electrolyte, but that’s not ‘simple’.)

No idea about the flickering lights. That sounds like a bad connection somewhere. First suspect is the isolator, especially if it’s one of those with the removable red keys. 

Thanks.  As it had been on charge on the mains for a few weeks, I can not see that the 100% in that case it would not actually be 100% as near as dam it, so if  itis really is fully charged is 14.8V OK?  I will try and measure the alternator current in the fully charged case next time we go out on the boat.

On the light I would not describe it as flickering that to me implies random, it was I think 5 flashes at say 1 second intervals, which seems very much like a signal (eg as the shoreline fridge does on under voltage).  I did check all the connections that I could and found nothing.

18 minutes ago, bizzard said:

Flickering lights before the eyes could mean a migraine's coming on.

Could mean anything!

34 minutes ago, Nickhlx said:

We have the Beta 43 which has an Iskra 175Amp domestic alternator, with Trojan wet batteries, and this is set to 14.8 volts so I guess its a chosen voltage by Beta for their alternator suppliers to configure. I think it is because it is high enough to not need frequent equalisation charges, and gives relatively quicker charge times for those who maybe don't cruise 24/7 (like us)...  The boat is now in its 9th year and still on the first set of batteries, although ready to replace this year...

 

It could be quite possible it has always been 14.8V, not sure I have ever looked before!

[WotEver]

1 hour ago, john6767 said:

is 14.8V OK?

Yep. Nice charge voltage, particularly in this weather. Always assuming that you have wet cells?  Not sealed batteries or gel?

Note that 14.8V is simply the alternator charging voltage and if you measure the batteries straight after charging they may well show 14.8V too but that’s known as ‘surface charge’. As soon as you start using the batteries (or leave them off charge for a considerable number of hours) that voltage will drop to 12.7V which is the true ‘full’ battery voltage. 

1 hour ago, john6767 said:

On the light I would not describe it as flickering that to me implies random, it was I think 5 flashes at say 1 second intervals, which seems very much like a signal (eg as the shoreline fridge does on under voltage).  I did check all the connections that I could and found nothing.

Sorry, I misread your original post and thought you were referring to the domestic lights, as in cabin lights. You mention ‘some kind of charge controller’, is the flashing light on this?  If so, it could mean lots of things, maybe ‘Batteries Full’?  Do you have a manual for it?

[john6767]

20 minutes ago, WotEver said:

Yep. Nice charge voltage, particularly in this weather. Always assuming that you have wet cells?  Not sealed batteries or gel?

Note that 14.8V is simply the alternator charging voltage and if you measure the batteries straight after charging they may well show 14.8V too but that’s known as ‘surface charge’. As soon as you start using the batteries (or leave them off charge for a considerable number of hours) that voltage will drop to 12.7V which is the true ‘full’ battery voltage. 

Sorry, I misread your original post and thought you were referring to the domestic lights, as in cabin lights. You mention ‘some kind of charge controller’, is the flashing light on this?  If so, it could mean lots of things, maybe ‘Batteries Full’?  Do you have a manual for it?

The batteries are normal lead acid ones, but sealed, ie you don't need to/can't top them up.

The 14.8V was measured with the engine still running, but does drop down to a more normal level quickly once you turn the engine off.

The charge controller on the domestic alternator is normal I think for Beta, I have found a bit of info on it in the Beta engine manual, I will post that tomorrow.  The light I was referring is the normal charge light on the Beta engine panel.  I did wonder if it we just some over voltage thing, given I only saw it when had come out of the marina, just I have never noticed it before, but as I mentioned the light its not very bright and I only saw it become it was almost dark, so perhaps it has always done that.

 

[sharpness]

2 hours ago, john6767 said:

The charge controller on the domestic alternator is normal I think for Beta, I have found a bit of info on it in the Beta engine manual, I will post that tomorrow. 

 

The Beta charge controller was discontinued quite a while ago. I was expecting one on our Beta 35 when we had our sailaway in 2002 but there wasn't one. I exchanged letters with Beta who said that it had been discontinued because of problems caused by user misoperation. The wiring diagrams etc are still in my copy of the engine operators manual.

[john6767]

8 hours ago, sharpness said:

The Beta charge controller was discontinued quite a while ago. I was expecting one on our Beta 35 when we had our sailaway in 2002 but there wasn't one. I exchanged letters with Beta who said that it had been discontinued because of problems caused by user misoperation. The wiring diagrams etc are still in my copy of the engine operators manual.

Interesting.  Ours is from 2005 and it certainly has a charge controller.  Looking in the engine  documentation online I found the following about the controller.  I need to have a closer look at it, not really taken much notice of it before, but it seems to say it has an led on it, but it would be underneath and impossible to see where it is mounted.  From the graph it look like it is expected to drop the voltage when the current has fallen below a threshold, so I will try and measure the current and see what that is doing. 

 

[sharpness]

14 hours ago, john6767 said:

Interesting.  Ours is from 2005 and it certainly has a charge controller.  Looking in the engine  documentation online I found the following about the controller.  I need to have a closer look at it, not really taken much notice of it before, but it seems to say it has an led on it, but it would be underneath and impossible to see where it is mounted.  From the graph it look like it is expected to drop the voltage when the current has fallen below a threshold, so I will try and measure the current and see what that is doing. 

Yes, as you say, interesting. As ours didn't have one I asked Beta to supply one & I would fit it, they refused.

[brassedoff]

My beta 38 did that but after running for a week it turn out to be damp within the alternator And the flashing light stopped.

 

[john6767]

22 hours ago, brassedoff said:

My beta 38 did that but after running for a week it turn out to be damp within the alternator And the flashing light stopped.

 

By “did that” which part do you mean.  Certainly in the initial case the boat had be stood for a few weeks in October so there could have been damp.  My plan is next time on the boat to try and measure current and voltage to see if when at 14.7V if is still taking current into the batteries.

[brassedoff]

From landline reading exactly 14.7volts, flickering red light  (leasure side). On first start up and cruising at 1200rmp.

Revs up to 1500rpm no flickering.

For my boat I think it was just damp only because it's fine when theirs no fog or super wet weather.  

I have a stern cruiser with boards/engine open to the elements.

I guess it might be moisture within the alternator.  (Only a guess)

[brassedoff]

Just to add, Beta engine's are renowned for week alternator mounting brackets/fixing points check all your bolts are tight.

[john6767]

8 hours ago, brassedoff said:

Just to add, Beta engine's are renowned for week alternator mounting brackets/fixing points check all your bolts are tight.

Yep done that, all good in that respect.  I will work on moisture as the reason for the flashing light at the moment as only seen on one occasion.