Electrical Plug Socket Making A Crackling Noise

Plug sockets power all the electrical appliances in our home and we seldom consider what is occurring behind the scenes. In this article we look at why a plug socket would make a crackling, popping or fizzing noise. We will also touch on maintenance and replacement advice along with safety tips.

1) What is plug socket crackling?

The noise that you hear is electrical current struggling to flow and intermittently making contact, jumping tiny air gaps causing arcing. Arcing is a dangerous situation where great heat is created as the resistance of the air is broken down, electrical current jumps the gap and can be the cause of electrical fires starting.

So, if you have a PLUG SOCKET CRACKLING then let us look at the most common reasons for this to occur:

• Loose wiring 
• Internal high resistance
• Water in the socket
• Damaged mechanism
• Corrosion problems

2) Loose wiring

Electrical connections and copper (or aluminium) wiring is subject to heat whenever electrical current flows and ambient temperatures change. The electrical supply is an alternating current supply meaning that there is also a tiny vibration on wiring at a rate of 50hz or 60hz. 

Metals expand and contract at different rates depending upon metal type and temperatures. 

There is also the action of inserting and removing appliance plugs that has a vibrating effect on cables and terminal connections.

All these factors can lead to tight connections becoming loose over time. When loose connections occur, there is a reduced contact area between cables and terminations or connections. This means that the electrical current struggles to flow smoothly as there is some resistance to the flow. 

When there is resistance, heat can build up and lead to a melted plug socket.

A loose connection is something that requires immediate attention to prevent electrical arcing from occurring or continuing.

3) Internal high resistance

Plug sockets are not designed to be installed and forever forgotten. All electrical accessories like plug sockets and light switches have a limited lifespan of a certain number of operations or years that they can survive for without issue. 

The wall sockets will eventually begin to wear out, build up dirt and debris internally and the internal metalwork can tarnish. These different issues can add up to mean a high resistance begins to develop inside the plug socket metals and connections. 

Any impedance to electrical current flow can eventually cause intermittent current flow meaning a high resistance and PLUG SOCKET CRACKLING. The sound of a plug socket crackling is worrying and can be seen visually in flickering lights where a table or floor lamp is connected to the electrical outlet.

4) Water in the socket

Where water enters an electrical outlet, a dangerous situation can be created. Water is partially conductive, or at least good enough to give electrical shocks or ruin electrical items by shorting them out. 

Water can bridge a gap between Line (HOT) and Neutral and create a path for electrical current to flow where it should not! The PLUG SOCKET CRACKLING due to water ingress is the sound of electrical current occasionally making its way between connections inside the plug socket. 

Should water enter a socket, the water sources should be stopped, the power supply shut off and the power socket replaced immediately. 

Without immediate action following water entry into the plug sockets, not only will the socket require replacement but the cables can become damaged through electrical burning and shorting out. 

Water in electrics can take some time to dry out and as a result, the power may need to remain off for some time in order to ensure the safety of the electrical system and to minimize the risk of electrical fires. 

5) Damaged mechanism 

Some plug sockets will have an internal shutter mechanism (UK for example) that requires the earth pin to be inserted before the Line and Neutral pins can be inserted. The insertion of the earth pin will release the shutters allowing the insertion of the other pins.  

This mechanism is a moving part inside the plug socket and is subject to wear and tear over time and use. What eventually happens with time, debris, dirt, and dust it that this mechanism becomes worn out and can jam up. 

A crackling sound or popping sound can occur in the socket if the mechanism jams and causes problems inside the socket. Short circuits can occur and create a situation meaning electrical current jumps gaps between electrical conductors. 

6) Corrosion problems

Over time, metal can tarnish, corrode, or rust. As the internal workings of a wall socket are comprised predominantly of metal, it is not uncommon for electrical problems to occur caused by rust or corrosion.

The most common causes of internal socket corrosion are moisture in kitchen and utility environments. There are of course other damp issues that can affect electrical circuits and sockets in other parts of the home. 

Rusty Sockets are a common issue in kitchens and conservatories. The issue is more prevalent where sockets are installed in outbuildings as moisture is not as regulated in these environments.

7) Will the circuit breaker trip the power off?

The fuse box (in older homes) or consumer unit will contain some form of protection for issues like a PLUG SOCKET CRACKLING. The circuit breaker or fuse will not necessarily operate to disconnect the electrical circuit in every situation however. 

With the most up to date modern technology in consumer units there are AFDD (Arc Fault Detection Devices) switches which can detect electrical arcing like a popping plug socket. 

Even with the most up to date technology there is no guarantee that the power will automatically disconnect in the event of these type of problems so it is best to quickly turn of the electrical supply yourself and seek assistance. 

8) Emergency Electrician Needed?

With buzzing sounds, crackling noises, an electrical burning smell, or other electrical problems, it is best to call a professional electrician immediately to find and repair the problem for you. A qualified electrician will be able to quickly diagnose and pinpoint the issue affecting your plug sockets. 

Leaving the problems to ‘fix itself’ never works and will likely result in significant damage occurring to the wiring system along with other potential hazards developing. 

9) Summary 

Whenever you experience buzzing noises from the fuse box, an electrical burning smell or a PLUG SOCKET CRACKLING don’t attempt to tackle issues yourself for safety reasons. 

These issues with wall outlets crackling are likely to require an experienced electrician to investigate the faulty wiring problems. Electrical work is fraught with hidden dangers and is a technical process that requires much compliance with regulations. 

If you have not had your power outlets or home wiring inspected in the last ten years or more then it is highly recommended that you have an electrical inspection carried out. This is the best way to ensure electrical safety and to discover any issues that are present.