Extended life of telecom relays by using SF/sub 6

The excellent dielectric characteristics of Sulfur-Hexafluoride (SF/sub 6/) are well known and have been applied for many years in high and medium voltage equipment and even in very small switches like telecom relays. The use of SF/sub 6/ in telecom relays increased the dielectric performance of relays although the dimensions were significantly reduced at the same time. Beside the improved dielectric performance, the electrical life and switching capability of the relays were significantly extended. On practically all tested loads at least the same, on many loads an extension of the electrical life could be found, e.g., maximum load, ringing load and others. Also the allowed switching range could be increased by a factor of two as the material transfer and erosion characteristics were improved significantly.