With NiCd, it peaks at a voltage drop of 1/256 of the actual voltage. This way it automatically detect how many cells there's in a pack.
So if your pack peak at 9,40 volt, the cut off will be 9,40 * 1/256 = 0,037 volt.
For NiMh the cut off are zero delta volt. But as far as I can see, the voltage drops a little anyway, before the charging stops.
Your charger are made by Apex. If you like, you can write to them for further information (that's the way I got this info). Their website: www.apexhk.com