BI Technologies (Fullerton, CA), a subsidiary of TT electronics plc (Patterson, NJ), recently developed a series of telecom line protection modules designed for T1/E1 line card circuits in central office and customer premises equipment applications, giving telecom systems design engineers a space-saving means of protecting up to 12 signal lines. The new modules provide both lightning surge and power cross protection that meets or exceeds the requirements of Telcordia GR-1089 and UL 1950 standards in a high-density package designed to conserve space on tightly packed line cards.
The new line protection modules can also be custom-designed to meet individual customer protection specifications. The design of the line protection modules features "self-resetting" line fuses, which eliminate expensive field service calls to replace blown conventional fuses. Integral surge resistors dissipate heat more effectively than leaded devices, and provide enhanced line balance, as they are batch processed on a common substrate for superior matching.
Typical protection levels are 120 Vac/25 A for power cross, and lightning surge (metallic) of 800 V/100 A for 2 µsec/10 µsec under the Telcordia GR-1089 and UL-1950 standards. Pricing for the line protection modules in telecom volume is approximately $1.50 per line, with availability from 8 to 12 weeks, depending on design.
