A system including a spinner assembly that includes a spinner subassembly which includes a spinner configured to engage a tubular, and a drive gear coupled to the spinner, with the drive gear configured to drive rotation of the spinner, and the encoder configured to count teeth of the drive gear as the drive gear rotates. A controller configured to determine a number of revolutions of a tubular that are needed to thread the tubular to a tubular string based on data from the encoder. The controller is also configured to determine when the tubular is unthreaded from the tubular string based on data from the encoder.