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EXERCISE 4
Operation principle of thermocouple
When hot junction is heated, a small amount of voltage will
be generated.
If the heat source is removed, the voltage will drop to zero.
The amount of voltage is very small. It is measured in
millivolts.
The conductors can be of any two dissimilar metals: stainless
steel and copper. This combination provides the right
amount of electrical energy necessary for a gas safety
system.
Stainless steel is used for the outer jacket of the
thermocouple.
Copper, combined with nickel alloys, is another metal known
for its excellent electrical conductivity.
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