Class A Electrical Equipment

4 1 class i equipment.

Class a electrical equipment.

A class c fire is an energized electrical fire. Class i equipment has a protective earth. Any place where electrical equipment is used or electrical wiring is present is a potential. Class ii equipment may also be manufactured with metal enclosures which are double insulated from live parts class ii equipment does not need an earth conductor and should not be earthed.

Sources of such hazards include gases vapors dust fibers and flyings which are combustible or flammable. Class c fires may begin from a short circuit faulty wiring power cord damage overcharged devices or overloaded electrical outlets. Energized in this case means that it is fed by a power source. For mains powered electrical equipment there are usually two levels of protection used called basic and supplementary protection.

This publication introduced eight modifications and additions to the classes of prescribed electrical equipment categories. Class i appliances are usually made of metal have three cables have a metal earth pin and have a fuse in the plug. The supplementary protection is intended to come into play in the event of failure of the basic protection. Electrical equipment installed in such locations could provide an ignition source due to electrical arcing or high temperature.

In addition to the equipment being suitable for the gas group and the temperature class required the type of protection must be suitable for the zone in. Most modern power tools and equipment which is subject to movement or flexing of the cord fall in to this category. These are now listed in appendix b of as nzs 4417 2 and take effect on 2 july 2018. Examples of class i appliances are refrigerators microwaves kettles irons and toasters.

However the only way to confirm whether the appliance is class i is to look for the class i symbol on the appliance. Each type of protection achieves its safety from ignition in different ways and not all are equally safe. There are ten recognized types of protection for hazardous area electrical apparatus. These appliances do not have their chassis connected to electrical earth.

These changes are as follows. Electrical equipment and devices within five feet of workstations in which flammable liquids or gases are used shall be in accordance with the electrical code for class i division 2 hazardous locations except when the air removal from the workstation or dilution will provide nonflammable atmospheres on a continuous basis ufc 5104 5. In electrical and safety engineering hazardous locations hazloc pronounced haz lōk are places where fire or explosion hazards may exist.