Page 264 - Electrician - TT (Volume 2)

ELECTRICIAN - CITS

6 Electric Iron

The main purpose of the electric iron is to press the clothes. Electric irons can be classified into two types as
given below:
• Ordinary electric iron

• Automatic electric iron
Ordinary Electric Iron
It consists of chromium-plated base plate, an electric heating element of nichrome wire fitted between the two
sheets of mica, a cast iron pressure plate, a chromium plated cover with insulated terminals and a handle. For
heating it is connected with the supply by means of a female connector having flexible cord and a three-pin plug
top. Figure shows the parts of an electric iron.
Electric iron

Laundry iron

The power consumption of domestic electric iron is 450 W while laundry irons (bigger in size, shown in Fig. 5.11)
are of 750, 1000 and 1500 W.
Automatic Electric Iron
In addition to the above mentioned parts, the automatic electric iron has a thermostat which is connected in series
with the element. This thermostat controls the temperature, prevents overheating of the iron and thus avoids
damage to the heating element. The necessity of the thermostat is due to the fact that some clothes like cotton
and linen require high temperature for pressing while terylene and silk require low temperature. The required
temperature can be obtained with the help of thermostat. The essential parts of an automatic iron shown below

Thermostat
The thermostat is a switch which-operates automatically due to the variation of heat produced around it. It functions
on the principle that different metals have different rates of expansion when heated. For example, brass has a
greater coefficient of expansion than iron. If a strip is made of bimetal (i.e., say brass and iron) and heated beyond
a certain temperature, it will bend downwards.

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CITS : Power - Electrician & Wireman - Lesson 101-103