Supply voltage from supplier side
Type of wiring installation done in the system
Current carrying capacity of installation
Type of wiring material used
Copper
Aluminium
Nichrome
Silver
Porcelain
Ceramic
Ebonite
Bakelite
Near the outer seating
Inside a hollow tube
Out side the body
Below the body
For the uniform distribution of heat
To prevent the heating element from coming out of grooves
To reduce the space for coiled heating element
To increase the resistance of the heating element