Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
CH Demand
Remove the mains supply to the appliance from the left hand side of the terminal strip and make safe
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

With the wiring to the appliance isolated does the mains power to the system establish or does the mains fuse still blow / RCD still trip?
Please choose one of the outcomes below:
FUSE NO LONGER BLOWS / RCD NO LONGER TRIPS
FUSE STILL BLOWS / RCD STILL TRIPS