Page 1 of 1

Charging stops after 60 minutes

PostPosted: Wed Sep 09, 2015 4:56 pm
by Frad
I have a sailboat with all the 1999 era Ample Power products including Alternator, Next Step Regulator, Emon-II, and Eliminator. Everything worked well for 14 years but then we had an alternator failure. After rebuilding the Ample Power alternator and reinstalling it everything seems perfectly normal at startup and for the next 59 minutes. Almost exactly 60 minutes after startup, charging then goes to zero. This problem continues to occur after almost exactly 60 minutes. In reading through the old manual on the Next Step Regulator, I noticed that the factory setting to go from Absorbtion to Float was 60 minutes. I don't believe we ever touched that dial. What are your thoughts on this? Could the Next Step Regulator be failing to go from Absorbtion to Float ?

I also measured temperature at the battery right after the problem occurred for the 2nd time thinking maybe something was getting hot. The negative post measured 89 degrees versus only 80 degrees at the positive post. Is this normal for the negative post to be hotter than the positive post ?

Re: Charging stops after 60 minutes

PostPosted: Wed Sep 09, 2015 7:36 pm
by Coulomb
The regulator is switching to float and the batteries don't accept charge at that level.

You have a bad connection on the negative terminal - perhaps internal to the battery.

Re: Charging stops after 60 minutes

PostPosted: Fri Sep 18, 2015 7:57 am
by Frad
Excellent call. A wingnut on the negative battery terminal that was getting warm was indeed a bit loose. That has been corrected and the problems seems to have been fixed. Thanks.

I now have it in my mind to adjust the regulator to stay in absorbtion mode for longer than 60 minutes since that seems a bit short for my bank of three 8D Gell-cells that total about 750 amp hours. Question: Does the engine need to be running when making this adjustment ? Also, how long in minutes would you recommend for my system that I set the absortion to float setpoint? Alternator is an Ample Power 200 A model. Thanks.

Re: Charging stops after 60 minutes

PostPosted: Fri Sep 18, 2015 4:50 pm
by Coulomb
The engine doesn't need to be running, but you need the ignition switch on to power the unit for adjustment.

You can set the timer this way:

Set the regulator absorption time to maximum.
Note the start time.
Run the engine and monitor battery current.
When battery current, in Amps, falls below 10% of capacity, in Amp-hours, note the time.

The time difference is what you should now set the regulator to.