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• CCITT Rec. K.21 (11/1988) – RESISTIBILITY OF SUBSCRIBERS' TERMINALS TO OVERVOLTAGES AND OVERCURRENTS
• RESISTIBILITY OF SUBSCRIBERS' TERMINALS TO OVERVOLTAGES AND OVERCURRENTS
• Introduction
• 1 Purpose of the Recommendation
• 2 Scope
• 3 Overvoltage and overcurrent conditions
• 4 Equipment boundary
• 5 Test conditions
• 6 Permitted malfunction or damage
• 7 Tests related to lightning surges, power induction and contacts
• 8 Tests related to electrostatic discharges
• 9 Tests related to mains-powered equipment
• References