Buzzing from the switchboard
A faint hum from a board can be normal. Loud buzzing, crackling, heat or a burning smell is not. Stop adding load and get it checked.
What to do right now
- Listen for where the sound comes from and when it happens.
- Do not open the board cover or touch any wiring.
- Switch off any large appliance that was on when the buzzing started.
- Text us a photo of the board with the cover closed.
It is an emergency if
Crackling, a burning smell, visible scorching or the cover feels warm. Switch off the main switch if safe, and call.
For fire, smoke, shock injuries or fallen lines, call 000 first.
Common causes
A loose connection
Arcing at a loose terminal buzzes and heats up. This worsens with time.
A failing breaker
Old breakers and fuse holders can hum or crackle as they wear.
Appliance noise
Some dimmers and transformers make a mild hum that is not dangerous.
What we do about it
We open the board safely, find the noisy part and replace it. If the board is old or damaged, we recommend an upgrade.
Common questions
Is a hum from the switchboard dangerous?
A very faint hum may be harmless. Anything loud, crackling or hot is a fault.
Can I tighten the connections myself?
No. Only a licensed electrician should open the board.