You can create a thermocouple designed to measure temperature or temperature difference at home. The only condition is the presence of chromel and copel wires. As you know, chromel is an alloy of nickel with chromium in a 90/10 ratio. Copel is an alloy of iron with nickel and copper. The nickel content in copel is 43-44%, iron is 2-3%, the rest is copper.
First of all, you need to understand that a thermocouple is a pair of conductors made of different materials, connected at one end and forming part of a device that uses the thermoelectric effect to measure temperature.
The most readily available alloys that can be used to obtain a thermocouple are chromel and copel, produced by our industry in the form of thin wires.
To get a working thermocouple, it is necessary to solder the chromel and copel wires. To do this, it is enough to take a battery "crown" or another one containing graphite electrodes, remove the rods from it and apply a small voltage to them, about 24V. When the graphite rods are connected, a glow will appear and heating will begin. Twist chromel and copel wires and place the junction between the graphite electrodes. The twist will melt and the knot will weld. The thermocouple is ready.
