High Speed Digital T1 or Leased Line Protector Protects up to one T1 or ISDN line per port using RJ48C/48S connectors. ISDN BRI/PRI compatible. Auto Resetting Technology PTC resistors open when a surge occurs, protecting your equipment, but unlike other fuses, the PTCs close again once the surge passes. Expandable modular system Applications T1, ISDN Agency Approval UL 497A Secondary Grounding Requirements Uses Electrical AC Ground Recommended Grounding Impedance 0.5 Ohm Signal Perfect Circuitry Auto Resetting PTCs 160 mA 8 10 Ohms Clamping Level 70V Response Time 1 5 Nanoseconds Capacitance 50pF Suppression Modes Metallic and Longitudinal Wires Protected 4 wires, 2 pairs per jack pins 1, 2, 4, 5 Termination Type RJ48C or RJ48S