Husqvarna PG680 Programming page 26

This display screen on the frequency inverter is on a timed window and
will return back to the standard "0" if left unattended for to long.
Both display screens should be at the same display "page" and ensure
both motors are connected before switching to RUN at the control panel.
A low pitched squeak can be heard as the frequency inverters synchronise with
the motors (this is normal). The Grinder should not start operating. If this
happens switch back to STOP and check the process again.
The display screen will return to the "0" once completed.
Press the Left arrow to return to P2
Press the Down arrow to return to M1