Investigation on the Switching Behavior of AgSnO2Materials in Commercial Contactors

The switching behavior of several varieties of Ag/SnO
2
contact materials was tested in commercial contactors and the results are compared with those obtained with standard Ag/CdO material. The properties tested were arc erosion under AC3 and AC4 conditions, contact resistance, temperature rise under continuous current, and making capacity. It was found that the newer Ag/SnO
2
-type materials, which contain WO
3
or MoO
3
in order to reduce overtemperatures, qualify as substitutes for Ag/CdO.