Some items are double insulated, thus they do not require earthing.
Earthing is done to make electrical appliances safe and secure, from immediate shock or lightning that may affect building.
Chemical Earthing and Conventional Earthing are different types of earthing techniques. Conventional Earthing is based on plate earthing and pipe type earthing but Chemical Earthing on GI or Copper.
The Indian Electricity Rules mandate that all electrical appliances and equipment must be grounded to ensure safety. The earthing system should comply with established standards to prevent electric shocks and to protect against power surges and faults. Regular inspections and maintenance of the earthing system are required to ensure its effectiveness.
At very first the load to be EARTHED before polarities to protect the load and human being
Electrical earthing is classified into many types as Neutral earthing Body earthing Pipe earthing Plate earthing Chemical earthing Ground Compound Earthing
For earthing pipe of 40mm dai & 3 mtr. Long required 5 kg. Of salt & 6.5 kg of charcoal. This type of earthing is done for distribution transformers of various rating.
Earthing is necessary for equipment safety and for human safety.Answer for USA, Canada and countries running a 60 Hz supply service.There are two types of earthing, they are:Plate earthing andPipe earthing.As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.Before you do any work yourself,on electrical circuits, equipment or appliances,always use a test meter to ensure the circuit is, in fact, de-energized.IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
earth wire will be connected to the part of appliance body at such a place which is in contact with earth (ground), so as to pass on the voltage into ground to make a big resistance to blow the fuse system behind, and to safe guard the user or human/animal from electric shock, if there is any leakage of current from appliance. K. S. Verma The earth wire should be connected to the outside case that comes in contact with people. That means that if live parts inside the device become connected to the case in a fault condition, enough current will flow to blow the fuse, instead of becoming dangerous to the users.
Earthing?
An earthing boss and earthing lug are parts of a grounding connection. An earthing boss is in a casting that allows for the drilling and tapping of hole. A earthing lug is used to bond a wire to the ground.
System Earthing is the earthing associated with current carrying conductor & is essential for the security of the system. Equipment Earthing is the earthing associated with non-current carrying metal work & is essential for the security of human life and property.
Some appliances are better adapted to batteries based on portability. Batteries allow significant portability. Appliances that remain in place, like a refrigerator, would not need batteries.