You would not want to use a pressure water extinguisher on any electrical fire due to the possibility of electricity being conducted through the water and injuring someone.
A CO2, dry chemical or "clean agent" (e.g., "Halogenated") extinguisher would be a better choice for an electrical fire, knowing that dry chemical powder will make quite a mess.
A Class C fire extinguisher should be used for electrical fires.
A water-type or water-based foam type of extinguisher should not be used on an electrical fire because water and foam are electrical conductors and could result in electrocution of the person using the extinguisher or anyone stepping in the water.
To pressurize a Sears dry chemical fire extinguisher model 958044, first ensure that the extinguisher is fully charged and that the safety pin is in place. Locate the pressure gauge on the extinguisher; it should be in the green zone. If the pressure is low, use a compatible air compressor or nitrogen tank to refill the extinguisher by connecting it to the fill valve. Always follow the manufacturer’s guidelines and safety procedures when handling fire extinguishers.
A water-type or water-based foam type of extinguisher should not be used on an electrical fire because water and foam are electrical conductors and could result in electrocution of the person using the extinguisher or anyone stepping in the water.
Neither a gasoline or electrical fire should be put out by water. A gasoline fire should be put out by a fire extinguisher labeled A B C. An electrical fire should first have the power switched off. Then the fire extinguisher should be used.
A class C fire involves energized electrical equipment. It should not be extinguished using water, as it can conduct electricity and cause electrocution. To extinguish a class C fire, it is recommended to use a dry chemical or carbon dioxide fire extinguisher designed for use on electrical fires.
Flammable metals often require special chemicals to extinguish, assuming there are any. So, in fact, you WOULD use a "chemical extinguisher", but probably not an ordinary dry chemical extinguisher.
Electrical fire is Class C as long as the electricity is on, so use a BC or ABC extinguisher, either dry chemical, carbon dioxide gas or halogenated gas.
you should use dry powder extinguisher
The extinguisher that has only a green triangle on it would be a really BAD choice because it probably contains water for putting out Class A fires of ordinary combustibles. An electrical fire (Class C) is signified by the letter C in a blue circle. Or, you can turn off the electricity and use any extinguisher appropriate for the type of fire that was started by the electricity's heat.
Anything with a class "C" rating
red = water and is used for wood paper textiles and solid material fires. DO not use on liquid elictrical or metal fires. blue = powder and is used for liquid and electrical fires. DO not use on metal fires. yellow = foam and is used for liquid fires. DO not use on electrical or metal fires black = carbon dioxide (CO) and is used for liquid and electrical fires DO not use on metal fires. halon can be used on all fires as well as dry chemical