Set Appliance State:
Mains Power Off
Set Multimeter to AC Voltage 
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Measure the Voltage across the Live (Brown) wire marked MAINS (L) and the Earth (Green/Yellow) wire on the main connector block.
Isolate as per TOPs P4
and refit as necessary