Experimental Studies of Load's Influence on AC Voltage Switches During Endurance Tests.

The important demand in the sense of safety and reliability in the area of domestic applications requires, for the improvement of switch devices, deeper knowledge on the influence of loads, particularly those including a capacity. These loads simulate fluorescent lamps (IEC 60-669-1). Switches shall withstand, without excessive wear or other harmful effect, the mechanical, electrical and thermal stresses occurring in normal use during their lifetime. The purpose of this work is the study, during endurance tests, of the influence of inductive load and inductive one witch including a capacity, on arc characteristics and contacts surface. The experimental tests have been done on switches with AgNi contacts and have been carried out under a rated alternative voltage of 250V and a rated current of 10A, for different numbers of opening/closing operations (from 500 to 5000). The main result shows that the peak arc current value for load containing a capacity reaches very high values at closing operations and is increasing with the number of operations. For inductive loads, it doesn't exceed twice the maximum rated current value and stays relatively constant at closing and opening operations. The observation of contacts surface with SEM after different numbers of operations, shows far more important and different damage of contacts with loads containing a capacity. [ABSTRACT FROM AUTHOR]