Lead way and requirements of thermal resistance

What way of thermal resistance of the wire is

the wires of a thermal resistance way has 3 kinds: namely, 2 wire and 3 wire system, four wire system.

2 line heating resistance wiring simple, but to bring in additional error lead resistance. So shall not apply to the manufacture precision of grade a thermal resistance, and in the use of wire and wire shoulds not be too long.

3 wire system can eliminate the influence of the lead resistance, the measuring accuracy is higher than 2 wire system. As the process of detecting element, its applied most widely.

4 wire system not only can eliminate the influence of the lead resistance, and the connection wire resistance phase at the same time, also can eliminate the influence of the resistance. When in high precision measurement, must use the four wire system.

requirement:

when three wire system wiring, three wire must: as long and thick, as the same material. Usually use three core or multicore cable;

to avoid electromagnetic interference. There is interference in place, can be used in metal officer, metal trough, using methods such as shielded cable solution;