QualifiedHigh risk

Intermittent dead or flickering load from a loose conductor

Lights or equipment on a circuit drop out, flicker, or come and go — sometimes with tapping, vibration, temperature, or load changes. The classic signature of a loose or partly-broken conductor.

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Safety first

Loose/arcing connections generate heat and are a recognised fire risk. If you find heat or scorching, treat it seriously. Isolate before opening accessories, and don't keep tapping a live arcing joint to 'find' it.

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.

Apprentice mode

Full walk-through — the why, what readings mean, mistakes & safety.

Likely causes

Ranked from most to least likely.

  1. 1

    Loose terminal at an accessory or connection

    Most likely

    A conductor not properly clamped (or a back-stabbed termination) makes and breaks with vibration, temperature, or load, dropping the circuit intermittently and heating the joint.

  2. 2

    Partly broken conductor strand

    #2

    A nicked or fatigued conductor with only a few strands left carries load until it flexes or heats, then opens — common where cables flex or were over-bent.

  3. 3

    High-resistance joint (corrosion / dissimilar metals)

    #3

    Corrosion or a poor aluminium/copper joint raises resistance, causing voltage drop, heat, and intermittent operation as conditions change.

  4. 4

    Loose connection at the switchboard

    Least likely

    A loose active/neutral at the breaker, neutral bar, or busbar drops everything downstream intermittently and can run dangerously hot.

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.

On the tools? Job Mode shows one test at a time with thumb-sized buttons — your place and readings carry straight over.

Enter Job Mode
Test 1 of 3
1

Map exactly what's affected to find the common point (one fitting, one circuit, or everything past a board terminal).

Expected reading

A clear common point where the fault must sit.

If it passes

The common point tells you where to concentrate the search.

If it fails

If the pattern is unclear, monitor voltage at the load while provoking it (tap/load/heat) safely.

Often leads toLoose connection overheating (discolouration / smell)Intermittent fault that's hard to reproduce
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View all expected readings at once
1. Map exactly what's affected to find the common point (one fitting, one circuit, or everything past a board terminal).
A clear common point where the fault must sit.
2. Safely isolate and inspect terminations at the common point and the switchboard for discolouration, heat damage, loose clamping, or a conductor that moves.
Tight, clean, undamaged terminations.
3. If terminations are good, check for a high-resistance/broken conductor: dead continuity/resistance tests across suspect sections, and look where cables flex.
Low, consistent resistance along the conductor.

Fault-finding flowchart

The same logic as a decision tree.

  1. 1
    start

    Intermittent dead/flickering load

    → step 2
  2. 2
    decision

    Do the affected loads share a common point?

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

    Are terminations at the common point / board sound?

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

    Monitor voltage at the load while provoking it safely to find the common point.

  5. 5
    decision

    Is conductor resistance low and consistent along the run?

    Yes→ step 7No→ step 8
  6. 6
    result

    Loose / heat-damaged termination — remake it and replace damaged parts.

  7. 7
    result

    Re-examine every termination including the neutral path.

  8. 8
    result

    Broken / high-resistance conductor — replace the affected section.

Common mistakes apprentices make

  • Tightening one obvious terminal and assuming the intermittent fault is fixed.
  • Overlooking the neutral side — a loose neutral causes the same symptoms.
  • Not checking the switchboard terminations when several things drop together.
  • Leaving a heat-damaged accessory in service after remaking the joint.

When to stop & escalate

Any sign of significant overheating or scorching means the connection (and possibly the cable) may be compromised — stop and investigate fully. Escalate if the broken conductor is in an inaccessible or concealed run that needs proper fault location.

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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Related faults

General testing

Loose connection overheating (discolouration / smell)

A terminal or connection is overheating — discoloured insulation, a burning smell, or heat you can feel — a common cause of nuisance faults and a real fire risk.

5 causes3 test steps
ApprenticeHigh risk
General testing

Intermittent fault that's hard to reproduce

Something fails occasionally — random trips, dropouts, or stoppages — but works fine when you go to look at it. The classic 'can't fault it on the bench' problem.

5 causes3 test steps
AdvancedMedium risk
General testing

Lost or high-resistance neutral

Strange symptoms across a circuit or installation — voltages going high and low on different loads, flickering, equipment damage — pointing to a lost or high-resistance neutral.

4 causes3 test steps
AdvancedHigh risk