ApprenticeMedium risk

Powerboard or extension lead not working

A powerboard or extension lead delivers no power, while the wall outlet it's plugged into is fine — usually the board's switch, its overload/reset, or a damaged lead.

Safety first

Damaged leads are a shock/fire risk — don't use a board or lead with damaged insulation or a cracked case. These are appliances, not fixed wiring.

Isolate, lock out / tag out, and prove dead before working unless a live test is specifically required, authorised, and carried out under proper supervision. Always follow local regulations, your site procedures, and the equipment manufacturer's documentation.

Full detail — causes, the why, and common mistakes.

Likely causes

Ranked from most to least likely.

  1. 1

    Board switch off / overload tripped

    Most likely

    The powerboard's master switch is off or its built-in overload/reset has tripped.

  2. 2

    Damaged lead or plug

    #2

    A broken conductor in the flex or a damaged plug stops power getting through.

  3. 3

    Wall outlet it's plugged into is off/dead

    #3

    The supplying GPO is switched off or faulty.

  4. 4

    Failed board (surge MOV / internal)

    Least likely

    A surge board can fail internally after absorbing a surge.

Reports are saved on this device to reflect what you actually find.

Testing sequence

Work through one test at a time. Expected reading and what each result means.

Test 1 of 2
1

Confirm the supplying wall outlet works (plug something straight in), and the board's switch/reset is on.

Expected reading

Wall outlet works; board switched on / reset.

If it passes

Supply and switch fine — check the lead and the board.

If it fails

Wall outlet off/dead or board switch/overload tripped — restore.

View all expected readings at once
1. Confirm the supplying wall outlet works (plug something straight in), and the board's switch/reset is on.
Wall outlet works; board switched on / reset.
2. Inspect the lead and plug for damage; test the board with a known-good appliance.
Undamaged lead/plug; board powers a good appliance.

Fault-finding flowchart

The same logic as a decision tree.

  1. 1
    start

    Powerboard/lead dead

    → step 2
  2. 2
    decision

    Does the wall outlet work and is the board switched/reset on?

    Yes→ step 3No→ step 4
  3. 3
    decision

    Is the lead/plug undamaged and does the board power a good appliance?

    Yes→ step 5No→ step 6
  4. 4
    result

    Restore the wall outlet / board switch or reset.

  5. 5
    result

    If still dead with good supply, the board has failed — replace.

  6. 6
    result

    Damaged lead/plug or failed board — replace it.

Common mistakes apprentices make

  • Not checking the board's own overload/reset button.
  • Using a board/lead with visible damage.
  • Assuming the board when the wall outlet is switched off.
  • Trying to repair a sealed powerboard instead of replacing it.

When to stop & escalate

Powerboards and leads are replaceable appliances, not fixed wiring — replace damaged ones. If the supplying GPO is faulty, that's licensed electrical work.

If you're past your competence, authorisation, or the safe limits of the job — stop and hand it on. There's no fault worth getting hurt over.

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