Electric toasters use nichrome wire coils that produce infrared radiation to toast bread. When powered, the nichrome wire coils heat up and glow red, radiating infrared energy that gently dries and chars the surface of the bread. The circuitry includes a simple timer using transistors, resistors and capacitors that cuts power to the heating coils and electromagnet that holds the bread after a set amount of time determined by the rate of charging of the capacitor.

1. Tod-Phod-Jod 1
By
Gourav Kalbalia

2. Toasters: The Inside Story 2

3. Electric Toaster
 It uses radiation to heat a piece of
bread.
 When you put your bread in and see
the coils glow red, the coils are
producing infrared radiation.
 The radiation gently dries and chars
the surface of the bread.
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4. Components of a Toaster
 The most common way for a toaster to create the infrared radiation
is to use nichrome wire wrapped back and forth across a mica
sheet.
 Nichrome wire is an alloy of nickel and chromium. It has two features
that make it a good producer of heat:
 Nichrome wire has a fairly high electrical resistance compared to
something like copper wire, so even a short length of it has enough
resistance to get quite hot.
 The nichrome alloy does not oxidize when heated. Iron wire would
rust very quickly at the temperatures seen in a toaster.
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5. 5Flow Chart of the Circuit

6. Circuit Board
Working
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 When you push down on the handle, the
plastic bar presses against the contacts
and applies power to the circuit board.
 Power runs directly through the contacts
to the nichrome wires to start toasting the
bread.
 A simple circuit made up of transistors,
resistors and capacitors turns on and
supplies power to the electromagnet.
 The electromagnet attracts the piece of
metal on the handle, holding the bread
in the toaster.
 The simple circuit acts as a timer. A
capacitor charges through a resistor,
and when it reaches a certain voltage it
cuts off the power to the electromagnet.
The spring immediately pulls the two
slices of bread up.
 In the process, the plastic bar rises and
cuts off power to the toaster.

7. Working
 Changing the resistance changes the rate
at which the capacitor charges, and this
controls how long the timer waits before
releasing the electromagnet.
 Changing the resistance changes the rate
at which the capacitor charges, and this
controls how long the timer waits before
releasing the electromagnet.
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8. Thank You
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