23
Fault Finding

Preliminary Electrical Systems Check

START
Isolate appliance
and carry out:
A: Earth Continuity
check.
Has inlet fuse blown?
Carry out:
C: Polarity check.
Electricity supply
should now be
satisfactory.
Carry out:
D: Resistance to
Earth check.
Inlet wiring
faulty.
Rectify any
fault.
Isolate appliance and
carry out:
B: Insulation check.
Rectify any fault
including replacing
fuses as necessary.

NO YES

SOCKET
(face view)
PLUG (with cover removed)
Earth Wire
Green/Yellow
Neutral Wire
Blue
( )
FUSE
( )
E
NL
NO YES
Brown Blue Green
Yellow
Green
Yellow
Brown
Blue