See page 12 of this manual.

[link=http://www.heliguy.com/i/ImaxB6manual.pdf]B6 Manual[/link]

You can also set your capacity higher than what the battery is rated at if you use peak or CV to determine the battery charge state.

I ran into the same thing with my Turnigy 4 port charger.

It's amazing the number of chargers being sold that are all based upon the iMax B6 circuitry.

I've counted over 20 different brands including:

Turnigy
Viper
Venom
Hitec
iMax itself
etc., etc., etc.

The prices charged for them vary GREATLY though they are basically the same thing.