ITU-T K.129 PDF

Silicon PN-junction surge protective components (SPCs) are special silicon diodes designed to limit overvoltages and divert surge currents by a voltage clamping action. This Recommendation applies to silicon PN-junction SPCs used in surge protective devices (SPDs) and telecommunication equipment ports to provide overvoltage protection for installations during lightning surges and alternating current (AC) power faults, in accordance with [b-ITU-T K.11]. Telecommunication equipment port test levels and criteria are defined by [b-ITU-T K.20], [b-ITU-T K.21] and [b-ITU-T K.45], as appropriate and are supported by [b-ITU-T K.44] with test circuit details and application guidance. In conjunction, [ITU-T K.103] should be read as it explains the parameters measured or verified in this Recommendation.

The following PN-junction component technologies are covered:

– Zener breakdown;

– avalanche breakdown;

– fold-back;

– punch-through;

– forward conduction.

This Recommendation contains information on:

a) terminology;

b) letter and circuit symbols;

c) essential electrical ratings and characteristics;

d) rating verification and characteristic measurement;

f) mechanical requirements and identification.