That's a peak charger with an automatic trickle charge (at 5% of charge rate) following the peak charge. Says the peak charge has a 90min limit, but apparently thetrickle will continue as long as the charger is left on.
If you're charging at 3amps and charger doesn't see peak correctly, you need to be around so the batt doesn't get overheated/damaged. Even if it peaks correctly there is a limit as to how long trickle charge can go on before it overheats the batta and damages it.
I wouldn't leave the batt on the charger.