Mike Krzyzewski is really a famous coach of Dream Team. She has coached north america men's basketball team for some time, that's clinched numerous medals for his country. Following Londonfl jerseys supplyn Olympic was over, Krzyzewski told The Associated Press that this game will be his final one as national coach, a job he's held for seven years. He had left open the possibility of swomen nfl jerseystaying with the team beyond the London Games, when practice on Saturday said these will be his last Olympics.When asked if he was sure, Krzyzewski didn't hesitate before again saying, "yecheap nfl jerseys wholesales," this will be his last game "If we could win it, then it might be three major championships in a row, i always do not know when that has been done because we haven't usually won http://govoriotkrito.bg/libs/nflcn08.htmthe globe championships," Krzyzewski said. "It becomes an enormous thing for the program." Whatever, he's an awesome coach. His achievement are going to be remembered by the country.cheap nfl jerseys
你的位置:首页 > 新闻动态 > 技术动态

交流接触器维护

2014/1/18 9:25:19      点击:
 交流接触器 维护①运行中检查项目:1)通过的负荷电流是否在接触器额定值之内;
2)接触器的分合信号指示是否与电路状态相符;
3)运行声音是否正常,有无因接触不良而发出放电声;

4)电磁线圈有无过热现象,电磁铁的短路环有无异常。
5)灭弧罩有无松动和损伤情况;
6)辅助触点有无烧损情况;
7)传动部分有无损伤;
8)周围运行环境有无不利运行的因素,如振动过大、通风不良、尘埃过多等。
②维护:
在电气设备进行维护工作时,应一并对接触器进行维护工作。
1)外部维护:
a.清扫外部灰尘;
b.检查各紧固件是否松动,特别是导体连接部分,防止接触松动而发热;
2)触点系统维护:
a.检查动、静触点位置是否对正,三相是否同时闭合,如有问题应调节触点弹簧;
b.检查触点磨损程度,磨损深度不得超过1mm,触点有烧损,开焊脱落时,须及时更换;轻微烧损时,一般不影响使用。清理触点时不允许使用砂纸,应使用整形锉;
c.测量相间绝缘电阻,阻值不低于10MΩ;
d.检查辅助触点动作是否灵活,触点行程应符合规定值,检查触点有无松动脱落,发现问题时,应及时修理或更换。
3)铁芯部分维护:
a.清扫灰尘,特别是运动部件及铁芯吸合接触面间;
b.检查铁芯的紧固情况,铁芯松散会引起运行噪音加大;
c.铁芯短路环有脱落或断裂要及时修复。
4)电磁线圈维护:
a.测量线圈绝缘电阻;
b.线圈绝缘物有无变色、老化现象,线圈表面温度不应超过65°C;
c.检查线圈引线连接,如有开焊、烧损应及时修复。5)灭弧罩部分维护:
a.检查灭弧罩是否破损;
b.灭弧罩位置有无松脱和位置变化;
c.清除灭弧罩缝隙内的金属颗粒及杂物。
5 真空交流接触器工作原理
真空接触器以真空为灭弧介质,其主触点密封在特制的真空灭弧管内。当操作线圈通电时,衔铁吸合,在触点弹簧和真空管自闭力的作用下触点闭合;操作线圈断电时,反力弹簧克服真空管自闭力使衔铁释放,触点断开。接触器分断电流时,触点间隙中会形成由金属蒸气形成的铂垢,影响接触器的使用寿命。