Battery charging problem

[Tony Brooks]

2 hours ago, cutandpolished61 said:

Hi Tony, 12v issue all sorted. It was the fuse. Got the adapters for the Hella sockets and have to use the inverter now much less.

One more problem turner up with my new 2500W generator. It's charging well at about 25amp per hour but the rev is going up and down. I thought it can't be the fuel filter on a brand new machine. Unable to find any other troubleshooting advise online.

First of all Amps per Hour is a nonsense. Amps is an instantaneous measurement of how many electrons are moving past a point in a circuit. Amp hours (Ah) is an indication of the time a battery can supply a given number of amps or the amount of electricity being delivered in a period of time.

 

I am not going back to the start of the topic to see if I can find out what type of generator this is. I seem to recall there may have been talk of a Perkins generator that had not been used for a long time but that might be in another topic. You say brand new so it makes me suspect this may be a portable petrol generator or a frame generator    running on petrol or diesel. What ever it is as its new the correct thing to do is to return to the vendor for replacement or repair under warranty. I am also unclear as to  where this charge is coming from. Is it from your Sterling charger that might be faulty, a separate mains charger connected to the generator, or somewhere else.

 

The varying speed may be a problem with the generatoir's speed control system or a fluctuating load that changes faster than the generator’s speed control system can  cope with.

 

If the speed is going up and down then unless its an inverter generator I suspect the frequency will be all over the place and that may damage equipment if it drifts too far away from 50 Hz. I am not sure how an inverter charger will cope with varying frequencies. You see not enough information about the is readily seeable.

 

The actual charge will be the maximum the set-up can deliver at first in the charging cycle but at a reduced voltage and then as the voltage rises it will be as much as the batteries decide they want. Nothing ca be gleaned for the 25 amps figure.

 

 

[cutandpolished61]

Thanks Tony for clarifying. It's a portable generator ( Boehmer W4500i ) which is running quietly. But as soon as I connect to the shore socket and switch on the sterling inverter charger the rev is going up followed by a constant rev fluctuation.   

[Tony Brooks]

8 hours ago, cutandpolished61 said:

Thanks Tony for clarifying. It's a portable generator ( Boehmer W4500i ) which is running quietly. But as soon as I connect to the shore socket and switch on the sterling inverter charger the rev is going up followed by a constant rev fluctuation.   

OK, so an Ebay or Amazon special.

 

Many of these inverter-generators have a slow and high speed switch so they run slower with low loads. Yours may have one or may do it automatically. That will explain why it revs up when it comes under load. If I were forced to guess, and I am far from confident this is correct, I would suggest its a fault with the speed control and it keeps on overshooting and undershooting the required speed although the sterling inverter might be doing something odd and loading it and unloading it. However if it were I would expect it to do it faster the the generator could respond.

 

Try it powering a resistive load, something like a small electric kettle or travel hair dryers and see if it does the same . If it does then I think its a generator fault.

[cutandpolished61]

I had to use the generator again and this time it was operating much quieter and with less rev fluctuation. I've contacted the dealer and in his opinion the generator would need a few runs to settle in. I have used the microwave and the rev didn't fluctuate at all. Will see how it goes today when I have to charge via the inverter again.

In the meantime the problem with the leisure batteries has resurfaced. I cruised before yesterday for 5 hours and the next morning the leisure batteries were flat. Perhaps you can help me to identify if the batteries are done, the alternator faulty or both. Currently the engine is running slight over idle. Gauge shows 12v. The power management panel shows 13.2v. Engine start sluggish. In addition I still have the problem with the Sterling Pro Reg BW making noise like a Geiger counter and indicating low voltage.

 

[Tony Brooks]

1 hour ago, cutandpolished61 said:

I had to use the generator again and this time it was operating much quieter and with less rev fluctuation. I've contacted the dealer and in his opinion the generator would need a few runs to settle in. I have used the microwave and the rev didn't fluctuate at all. Will see how it goes today when I have to charge via the inverter again.

In the meantime the problem with the leisure batteries has resurfaced. I cruised before yesterday for 5 hours and the next morning the leisure batteries were flat. Perhaps you can help me to identify if the batteries are done, the alternator faulty or both. Currently the engine is running slight over idle. Gauge shows 12v. The power management panel shows 13.2v. Engine start sluggish. In addition I still have the problem with the Sterling Pro Reg BW making noise like a Geiger counter and indicating low voltage.

 

"Gauge shows 12v. The power management panel shows 13.2v. Engine start sluggish"  so what battery bank are they connected to? If I remember correctly you have three banks - start, domestic. bow thruster & fridge, although from this topic I am not confident that is actually correct.

 

If the engine is sluggish when  the starter is operated it suggests the start battery is discharged and if the "gauge" is on the start battery I am not surprised. 12V open circuit reading is all but fully discharged and when cranking I would expect the voltage to be very low, maybe around 8 volts or less.

 

I believe some day ago I suggested some of your symptoms might be related to shorting battery cells but you said the typical "easy to test" symptoms or some cells using a lot of water/being dry, the whole or part of batteries getting hot when under charge, excess gassing and a rotten egg smell  were not present. Are teh ends of any batteries bowing out or have any batteries got a bulge/tilt in the top?

 

You should not do battery charging at anything like tick over. I would suggest 1200 to 1500 rpm.  You maybe able to gradually reduce the speed as the charging current drops.

 

What is the charging current (amps) shown on the monitor and the charging voltage. A series of readings every half hour or so over six hours would go a long way to diagnosing the alternator. However that will only tell us about the bank the monitor is connected to.

 

If you have wet open cell batteries (bet you don't) then post the hydrometer readings and acid colour from each battery cell here plus the rested voltage reading with no load applied. That should tell us how sulphated the batteries are.

 

If the batteries are sealed then it is much  harder for a live-a-board but the basic procedure is:

 

Remove a battery or batteries form the bank.

Fully charge it and when done leave it to stand overnight.

Measure and note the voltage.

Leave to stand for about a week but you can test every day.

Measure and note the voltage.

 

The two voltages should not vary by more than a very few tenths of a volt. If the second reading is much lower then you have shorting cells in the battery.

 

 

Basically its the batteries that determine the charging current they want except when that current is higher than the charge source can supply. In that case the charging voltage will be pulled down but gradually rise as the batteries charge and demand less current. From this you can see a low charging voltage may be caused by a fault with the charging source or the batteries demanding too high a current from that particular source. Running an alternator will also reduce its ability to supply its maximum output so a low charging speed can also give low charging voltage.

 

I very much doubt the forum can do anything more to advise you because we still are not 100%  sure about your systems and how they are supposed to work and there are too many variables to pin the blame on a particular item. 

 

 

 

 

 

 

 

 

Edited August 1, 2019 by Tony Brooks

[Graham Davis]

In the list of 5 actions above I think Tony means NOTE the voltage.

[Tony Brooks]

10 minutes ago, Graham Davis said:

In the list of 5 actions above I think Tony means NOTE the voltage.

Thanks for noticing, Now edited.

[cutandpolished61]

Well I had to read your e mail 3 times and still don't understand the content fully. I simply struggle to catch up with all the info I receive. But I understand now more than 3 weeks ago which is positive. The two 110 amp leisure 12v batteries are now basically dead. Charged this morning with the generator for 2 hours and just charging a couple of laptops and mobile phones after and the batteries are flat. Nothing works on 12v now.  Engine still starts although sluggish. As soon as the engine starts all the 12 v appliances can be used instantly. The battery simply doesn't hold any charge, not for 1 hour. Tomorrow i'm off to Northold Boat Yard.  I'm almost certain that the faulty sterling alternator regulator is to blame for the failure. As mentioned before on my trip from Great Haywood to London I noticed a power surge on the gauge when the reading went up to 18v for a few minutes. At the same time the engine rev went down by 100 revs. Then the reading came back to 13.5v or so  and the rev increased again. This happened 5-6 times throughout the trip.

[Alan de Enfield]

7 minutes ago, cutandpolished61 said:

Charged this morning with the generator for 2 hours and just charging a couple of laptops and mobile phones after and the batteries are flat. Nothing works on 12v now.

Charging for 2 hours is no good - they probably need 12+ hours.

I have lost the 'plot' in this thread - do you have a 230v battery charger that you are running off the generator, or are you using the 12v output from the generator ?

[MtB]

38 minutes ago, Alan de Enfield said:

I have lost the 'plot' in this thread -

 

Same here. No-one (not even Tony) can give the OP any meaningful advice without a proper list of exactly what equipment is installed in the boat. Photos of EVERYTHING including chargers, inverters, alternators, generators, instruments and battery banks and all isolating switches would be the starting point for unravelling and making sense of all this. 

 

Over to you, OP. 

 

 

 

Edited August 2, 2019 by Mike the Boilerman
Add a bit

[Tony Brooks]

8 minutes ago, Mike the Boilerman said:

 

Same here. No-one (not even Tony) can give the OP any meaningful advice without a proper list of exactly what equipment is installed in the boat. Photos of EVERYTHING including chargers, inverters, alternators, generators, instruments and battery banks and all isolating switches would be the starting point for unravelling and making sense of all this. 

 

Over to you, OP. 

 

 

 

And EXACTLY what the OP is doing and what any readings actually relate to.

 

I suspect its time to pay up and get professional help.

[WotEver]

44 minutes ago, Alan de Enfield said:

do you have a 230v battery charger

Yes he does - Sterling Combi. We don’t know which one but we do know he’s seen 25A charging current. 

 

I suspect his batteries are dead through abuse but there’s little point replacing them until we can ensure that OP has grasped some fundamentals. 

Like charging for 2 hours achieves nothing.