Explain iron and silicon iron alloys.
Iron: Galvanised steel and iron wires that are usually used for earth conductor in low voltage distribution systems may also be utilized for the phase conductor in rural regions. Cast iron is used in the manufacturing of 'resistance grids' to be used in the starting of huge dc motors.
Silicon iron alloy: Pure iron has low resistivity that results in higher eddy current losses. Such losses can be minimized through increasing the resistivity of the material that is achieved by adding from 1 to 4 percent of silicon to iron. Silicon raises the electrical resistivity of iron. This reduces hysterisis loss. The magnetostriction effect is also decreased. Silicon iron alloy is utilized in the form of thin sheets termed as laminations. These laminations are utilized in small machines, huge turbo generators and transformers.