Fault Finding
Preliminary Electrical Systems Check
START
Isolate appliance and carry out:
A:Earth Continuity check.
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| YES | Carry out: | |
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| B: Insulation | ||
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| NO |
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Has inlet fuse blown?
NO | YES |
Inlet wiring faulty. Rectify any fault.
Isolate appliance and carry out:
B:Insulation check. Rectify any fault including replacing fuses as necessary.
Brown Blue Green
Blue
Brown Green
Electricity supply should now be satisfactory.
A. EARTH CONTINUITY CHECK
Appliance must be electrically disconnected - meter set on W (Ohms) x 1 scale and adjust zero if necessary.
a)Test leads from any appliance earth point to earth pin on plug. Resistance should be less than 0.1W (Ohm),check all earth wires for continuity and all contacts clean and tight.
B. INSULATION CHECK
Appliance electrically disconnected, all switches ON.
a) meter set on W (Ohms) x 1 scale. Test leads from L to N in appliance terminal block. If meter reads «0» then there is a short circuit.
b) meter set on W (Ohm) x 100 scale.
Repeat test with leads from L to E. If meter reads less than ¥ (infinity) there is a fault.
NOTE - Should it be found that the fuse has failed but no fault is indicated - a detailed continuity check (i.e. by disconnecting and checking each component) is required to trace the faulty component.
It is possible that a fault could occur as a result of local burning/arcing but no fault could be found under test. However a detailed visual inspection should reveal evidence of burning around the fault.
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