Erosion Phenomena for AgNi and AgSnO2 Contacts in A.C Low Voltage Switches
The reliability of low voltage switches isverified by endurance tests (CEI- 60669-1). The mostimportant problems are excessive wear and erosion orother harmful effect occurring in normal use, because ofpresence of electrical arc during making and brakingoperations.The subject of this work is experimental study of erosionphenomena of switches electrical contacts during theirlife.Tests are done for a.c switches with a rate voltage (250V)and a rate current (16A), and with AgNi and AgSnO2contacts. Switches are tested with inductive loads(cosφ>=0,6 and cosφ=0,3) and are subjected to 30000operations at a uniform rate of 15 openinig-closingoperations per minute.Based on contact mass variation during endurance tests,different behaviours have been observed for AgNi andAgSnO2 contacts.In switch endurance tests, contamination of contacts bycarbonaceous deposits, coming from internal electricallyinsulated box of the switch, by a thermal phenomenondue to electrical arc, has masked contact mass loss andhas shown magnitude and importance of thisphenomenon.
Reliability switches contact AgSnO2 AgNi
L.Chaabane M.Sassi
Electrical Department-National School of Engineers, 1002 Tunis, Tunisia The Petroleum Institute, Abu Dhabi, UAE
国际会议
温州
英文
112-114
2009-10-18（万方平台首次上网日期，不代表论文的发表时间）