Every scan will cause an outgoing query, for most sensors types it will require a TCP connection which needs to be established with the target host, the results need to be received and than stored in the database. Then, the measurements need to be processed to see if any thresholds were exceeded. This does not work within a second, therefore, we only support intervals of 10 seconds and above.
Most manufacturers do not update the interface counters in very low intervals. Therefore, one minute intervals will be sufficient since these sensors will calculate the delta to the last measured value.
Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.