FTP test using LeMond Revolution and Wattbox

Morning

I ran my first FTP test on Zwift yesterday and wanted to check a couple of things. I was using the Wattbox for power and it appears to estimate the cadence. How does the cadence figure affect the estimated power?

My previous FTP on a Wattbike was considerably higher than experienced yesterday. I’ll try and run a comparison FTP on Zwift using the powermeter on my bike rather than the Wattbox on the LeMond. I assume that might be better/more accurate?

Thanks

cadence is dependant on what gear you want to use for your ftp.

high gear potentially lower cadence

low gear really fast cadence to generate watts.

the wattbox is basically a speed sensor that uses a set algorithmin to determine watts.

Keep in mind wattbox is typically where power is lost due to drivetrain losses.