The white powder on electrical wires is caused by moisture and corrosion.
However if the white powder is the entire length of the electrical wire then it's talcum powder that is used to prevent the insulation from sticking and protect against corrosion and moisture.
Powder on cables can be talcum powder unless the powder is just suddenly appearing.
If the powder including white powder, green powder or blue colored powder suddenly appears on the cables wire then it's corrosion.
However talcum powder is used in some cables inside the insulation to prevent the wires from sticking and allow more flexibility.
In low voltage cables and other kinds of cords the white powder is often just talcum powder, which is used in some low current and low voltage cables.
The talcum powder is added the inside of some cords to make the cord for flexible and prevent the internal wires from becoming stuck to the outer rubber casing.
When the cable is used over a long period of time, the cables outer rubber becomes sticky and can be broken down.
Cable greening is bad as it indicates that there is degradation in the cables insulation and can potentially lead to increased electrical resistance, short circuits and even fire if left without fixing.
Cable greening can be caused by overheating or a chemical reaction between the cable's insulation and other material or even from corrosion of the copper wire inside the cables insulation.
Cable greening can also appear inside cables and leak out of them and can be caused by the decomposition of the plasticiser in the cable's insulation.
It can occur when the cable has loose connections, is overheated or is overloaded.
The green substance is conductive and can be dangerous.
Electrical cables can cause a fire if they are damaged, corroded, overloaded, frayed, worn out or are fitting loose in the outlet.
A loose outlet can also start a fire when the plug does not fit snugly into the outlet and leads to resistance.
If your plug feels hot and the cord is loose in the plug then the outlet needs replaced.
A damaged cable can start a fire, especially if the damaged cable has exposed wires.
The exposed wires of the damaged cables can make contact with each other and start a fire when they short out and they can also shock you as well.
Cords with damaged insulation or damaged plugs should never be used and should be replaced.
Things that can damage electrical cords are pulling them out of the outlet without grasping the plug, bending the cord, aging, abrasion, walking or driving on electrical cords, mechanic stress, overheating and overloading the electrical cords.
The most common cause of cable failure is damage to the insulation.
Damage to the cables or wires insulation can occur from aging, bending, abrasion and mechanical stress.
Over time as cables age the insulation can break down and start to crack and even come part which makes the cable no longer safe for use with electricity.
Electrical overloading can also damage the insulation on cables and wiring and cords as the overloading of the wires and cables can melt the insulation and start a fire.
Wire corrosion can look like a flaky layer of discoloration that can be green brown or white, especially on battery terminals and a general discoloration on other electrical wires.
Corrosion also weaken the integrity of the wire and make it more likely to fail and even be a fire hazard as the corrosion wires can cause electric failures.
Wire corrosion can look either white and powdery or even green or blue depending on the wire and the corrosion.
The wires in cables such as copper can develop a powdery substance that is lead sulfate when it's white and copper sulfate when the powdery substance is green or blue.
The copper in the wires is being eaten away, which leads to excessive electrical resistance and can voltage loss.
Cables are coated in plastics like PVC, polyvinyl chloride, nylon or polyethylene for insulation.
A popular coating and insulation for cables that are used outdoors is PVC as it's resistant to heat, UV rays, water, acids and alkalies.
Polyethylene is used as a protective cover and insulation for electrical cables as it's resistant to impact and abrasion.
Nylon is also a popular coating material for some cables as it has a melting point of 180 F.
Aluminum is also used in shielded cables to protect the internal wires from electromagnetic disturbances and interference.
Some cables are also coated in a layer of talcum powder that is applied inside the cable jacket to act as a lubricant and separate the individual wires and improve flexibility during movement.
It's a common practice to coat cables in a layer of talcum powder when they have multiple conductors inside.
Talcum powder is sometimes used in some low current low voltage wires like computer power cables to make them more flexible and to stop the internal wires from becoming stuck to the outer rubber casing.
When cables are used over a long period of time the outer rubber can get sticky and break down.
The wires in cables such as copper can also develop a powdery substance that is lead sulfate when it's white and copper sulfate when the powdery substance is green or blue.
The copper in the wires is being eaten away, which leads to excessive electrical resistance and can voltage loss.