The maximum sampling rate possible with the USB ADC-11 is 20 ksps (15 Ksps parallel ADC-11), however, that is divided by the number of active channels.
Also, the ADC-11 and the PC both have performance limits and will rarely be able to give exactly the settings that are requested. In block mode, PicoLog will attempt to negotiate the requested settings based upon one of two user options:
a) The total collection time remains constant - Here, the time will remain very similar to that requested and the number of samples will be compromised.
b) Number of samples remain constant - Here, the number of samples will remain very similar to that requested and the collection time will be compromised.
In practice, you could prioritise the collection time for 3-4 seconds and PicoLog will collect the best number of samples possible in that time. Alternatively, you might prioritise the number of samples required and PicoLog will collect those in the best possible time.
In single channel Scope mode, you could typically expect to measure up to around 7KHz, (sine wave assumed) though the displayed waveform would be poor, or, around 1.5KHz with reasonable sine shape.