| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a characteristics adjustment method for a thermal overcurrent relay, which can restrict variations in characteristics adjustment to improve adjustment accuracy and productivity. <P>SOLUTION: A target difference in displacement amount which is a difference in displacement between a main circuit bimetal and a temperature correction bimetal when these pieces of bimetal are temperature saturated by applying a UTC (Ultimate Trip Current) at each of minimum, middle and maximum scales, is respectively calculated in advance. Then, excessive heat is applied to the main circuit bimetal in a short time after electric conduction started and, thereafter, the heat applied to the main circuit bimetal is reduced, and within a stable time range where a difference in displacement amount between the two bimetals is near the target difference in displacement amount at each scale, a forcible trip is exerted. That way, characteristics adjustment at each scale position is carried out. <P>COPYRIGHT: (C)2013,JPO&INPIT |
