Thanks dragon, that is what Dave M said. Dim light goes to trickle charge. I feel that my concern has been answered and I thank all who contributed by sharing their knowledge and experience.

Regards Glyn.

HI Glyn
It may help I have a Ansmann ALCS 2-24 A.
When red light goes dim its on trickle charge at 20mA
never have any problems with any of the btys.

HI Lee;

Thanks Lee, you having the same gear and symptoms but without any problems makes me feel more confident. I hope that I can make some one feel that way in the future.

This is a super site built by super people.

Regards Glyn

HI glyn I have had the same problem, same 12v charger and same 12v 7amp battery I have the 6 volt charger as wellsame problem charging that red light never seem to go out, but never had any problems with the battery's holding there charge, regards Lee.

HI Glyn
Sounds like the charger is working OK. When the red led goes dim the voltage should drop to about 13 v which your meter should be able to indicate.
To test the batteries you need to put them under a heavy load (high current motor) or use in your model in the water. The info so far suggests all will be OK.
Dave

HI Dave,

Thanks for that info it answers my concerns. Of cause if the manufacturer of the charger had produced more accurate information this question would not have arisen. I will however keep an eye on the batteries. The readings are the same on both units, and during charging the meter said nearly 15 volts. My meter is not digital and not so accurate to read.

Regards Glyn

HI Glyn
Fully charged is 13.5 volts to 14.25 volts so if this is the voltage under load the battery has been charged. if it has stood unused for a period you may need to cycle through the charge discharge process a few times to bring to full capacity.

Could be the dim light indicates the charger is trickle charging the battery which is how burgular alarm batteries are maintained. if you check the battery voltage with your meter only whilst the charger is attached and switched on you should get 14.25 volts if charging is taking place (red light on) but this will drop to a constant 13.5 volts when charged indicating the trickle maintenance charge. Depending on your meter you may get slightly different readings but they should be the same for both batteries.

HI Alan & Dave,

Thanks for your response. I will do as you suggested. Have tested about 48 hours post charge about 13Volts. Will recharge and repeat test 24 and 48 hours and see what I get. Will also test under load.

Thanks & regards Glyn

HI Glyn
Just a quick though in addition to Alan's advice. You are charging the batteries separately? The auto charge process measures the internal resistance to determine the full charge and as most batteries have different characteristics this can lead to unbalanced results.

To obtain a useful reading with a voltmeter I suggest you also add a load to the battery, a bulb or motor connected across the terminals will suffice. Without such a load the battery will give a higher open cell reading which may drop considerably on load.

Finally faulty batteries can gas and give off an explosive gas so I suggest you conduct the tests in a well ventilated area remote from the charging point.

When you have charged one or both of your batteries (to a dull shimmering light) let the battery rest for an hour, take a voltage read with a multI meter, make a note, then take voltage readings 24 and 48 hours later to see if they are holding their charge. Post results on here.
Its unlikely the batteries are at fault, the first reading should tell if the charger is working.

Alan