Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Set Multimeter to AC Volts Set meter to measure AC Volts
Remove control box cover
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Measurement:

Measure the incoming mains voltage across the brown lead (live) and the blue lead (neutral) before the fuses on the terminal strip.
Expect mains voltage.
Note:
On some appliances the incoming terminal strip is located differently and has been rotated through 180° from the one shown.