Overcurrent Device Prevents Telecom Faults

The TSM600-400 is a low-resistance, re-settable, over-current protection device for communications infrastructure applications. It contains two matched, low-resistance PPTC (polymeric positive temperature coefficient) components in a single package for balanced resistance characteristics. Typical resistance is 1.2Ω, matched to better than 0.3Ω. It is intended for grounded communications systems such as POTS and xDSL line cards. When combined with thyristor surge protectors or gas discharge tubes, the system complies with the lightning and ac power-fault protection requirements of Telecordia GR-1089, Issue 3, scheduled to go into effect in 2006. Rated hold current is 400 mA at room temperature. The operating temperature range is -40ºC to +85ºC. Price is $1 each/100,000. TYCO ELECTRONICS POWER COMPONENTS, Menlo Park, CA. (800) 227-7040.