sbr, it will depend on what the charge rate is set at. ie C5, C10 etc. This means the battery capacity divided by a factor of 5, 10 etc.

Take a 1000mAh battery pack and programme the swallow to charge at C10, this means it should be charging at a theoretical 100mA of current.

From a dead flat battery theoreticaly it should take batt capacity/charge rate 1000/100 = 10 hrs. In theory that is. Many vaiables that can change that but you get the general idea.

First off find out the type of battery you have, make model etc then find out the manufacturers recomended charge and discharge rates. Programme the swallow accordingly.

I've only just bought one of these chargers so have not had the chance to play with it yet, my other charger is a Smart Fast Charger from that mob in Tassie.
hope this helps

cheers
Peter