Electrical – Source of periodic buzzing noise in the walls

electrical

Just moved in to a new place and I've noticed during the quiet of the night when trying to sleep that there is this periodic electrical sounding buzz, sort of like the hum of my subwoofer if I leave it on with no audio input.

I've timed its frequency, and the sound persists for 1 min 25 seconds every time, and then switches off for about 1 min 15 seconds.

It isn't only at night either; it's just that noises of the day usually drown it out. It seems to persist all day.

Anyone had experience with something like this and could help me identify the source? I can't quite locate the exact source of it, but it sounds like it may be coming from the place above me.

Thanks!

Best Answer

My only experience with unknown buzzing sounds was when a tenant complained of similar sounds. Upon investigating I discovered a honey bee colony had made a nest inside the board and batten wall. I was fortunate enough to find an apiarist (bee keeper) that relocated the bees to his orchard for free.

Related Solutions

Electrical – AC/DC adapters making strange buzzing crackling noise in all house, what causes it

You have an arc-over somewhere in your power supply system. Electric arcs produce a broad band signal with precisely that noise pattern.

Cracked or dirty insulators on the power poles, transformer with an internal primary circuit fault, loose connections between the transformer and meter, or compromised underground feeder cables that are leaking current between the conductors will probably be the source of this EMI.

Heaven forbid that the source is anywhere in the house, that's a dangerous situation.

Determining where it comes from

Given the noise that can be heard in the video, this should be transmitting a pretty nasty interference on AM radio frequencies to the point you should have no problem using an AM radio as a source detector.

First steps are to make sure this isn't something in the house that is suffering from a loose connection, ground leakage or arc fault. Turn your radio on and with it somewhere mid band between stations, see if you can hear the noise. Now go through the breaker panel or fuse panel and cut power to each circuit till you have cut all power to the house.

If the noise goes completely away from powering off a circuit, then start looking for appliances, switches, lighting fixtures powered by that circuit that that have failures. At this point, if wiring starts being the possible culprit, you're getting into electrician territory, so get a qualified electrician if you're exceeding your technical expertise or what you're allowed to do under your local laws.

Using this method, I had found that the people who wired my house up had used a crimp ground ring to complete a power circuit in the bathroom which explained the radio noise and the dim lighting that would flicker every so often. Removing the electrician's tape off the odd looking connection revealed that the crimp ring (improper use, only supposed to be used in the ground circuit) had worked loose and the copper wire was being slowly eroded from the arcing in the loose connection.

If the power down only slowly diminishes the noise till the last circuit is cut off, then you need to make sure the power entrance and cabling to the breaker panel/fuse panel are intact to clear your residence (qualified electrician time, you do not want to be messing with this).

Once you have cleared your residential wiring, then you need to get the power company involved in hunting down where the noise is emanating from. It's in their best interest to fix it if its a bad splice, cracked insulator or transformer getting ready to blow.

Electrical – Is this buzzing noise coming from various outlets around the house normal

Transformers

The sound you're hearing, is likely caused by transformers. It's a common problem, and a normal phenomenon.

Most wall warts consist of a transformer to reduce the voltage, and a rectifier to convert alternating current to direct current. So anywhere there's an AC adapter, there's likely a transformer.

This document from Federal Pacific (PDF), explains the phenomenon that causes transformer hum well.

Transformer noise is caused by a phenomenon called magnetostriction. in very simple terms this means that if a piece of magnetic sheet steel is magnetized it will extend itself. When the magnetization is taken away, it goes back to its original condition....

A transformer core is made from many sheets of special steel...

If the extension and contractions described above are taking place erratically all over a sheet, and each sheet is behaving erratically with respect to its neighbor. You can get a picture of the moving, writhing construction when it is excited. Of course, these extensions are only small dimensionally, and therefore cannot usually be seen by the naked eye. They are, however, sufficient to cause a vibration, and as a result noise...

Loose Connections

If you're hearing the buzzing from receptacles (sockets), it could be caused by a loose connection. If a connection in the receptacle is loose, there could be arcing taking place. Arcing could definitely cause an audible sound. However, arcing would also generate heat, which could lead to a fire. It's best to contact a local Electrician to come have a look. If you're familiar and comfortable with electrical work, you could check the connections and/or try replacing the receptacle (socket).