Issue link: https://resources.mouser.com/i/1442796
• Guarantee a good quality of service (QoS) for high speed data services by issuing requirements on characteristics of copper cables and on the coexistence of services delivered by different providers. Topics for the term "circuit protection" are found in recommendations from the K series. Recommendations and the Structure When reviewing the structure of recommendations, it is important to note that the letter designation reflects the time of issue (the higher the letter, the more recent the recommendation was published). Plus, the recommendations are regularly reworked where new issues are added to the existing K designation. A short overview of select recommendations relevant to circuit protection are shown in the following table: | 27 | K Number K Title Description/Related To K.20 Resistibility of telecommunication equipment to overvoltage and overcurrent Tests applicable for CO K.21 Resistibility of equipment installed in customer premises to overvoltage and overcurrent Tests applicable for CPE K.45 Resistibility of equipment installed in the access and trunk networks to overvoltage and overcurrent Tests applicable for access and trunk equipment K.44 Resistibility tests for equipment exposed to overvoltage and overcurrent Gives details and test setup diagrams for the above three (CO, CPE and access network) K.12 Characteristics of gas discharge tubes for the protection of telecommunications installations General tests for characterization of GDTs K.50 Safe limits for operating voltages and currents of telecommunication systems powered over the network Provides guidance on voltages and currents that may safely be used to power telecommunication systems K.51 Safety criteria for telecommunication equipment Provides guidance on safety criteria for telecommunication network infrastructure equipment K.99 Surge protective component application guide - Gas discharge tubes GDT application guide K.67 Expected surges on telecommunications and signaling networks due to lightning Discusses different lightning events as this threat relates to all three types of the equipment installed (CO, CPE and access network) K.98 Overvoltage protection guide for telecommunication equipment installed in customer premises Provides methodology for evaluating the need to protect users of telecommunication equipment in CPE K.102 Parameters of fixed-voltage thyristor overvoltage protector components used for the protection of telecommunication installations Provides fixed-voltage thyristor parameters to ease the choice for designers K.103 Surge protective component application guide - Silicon PN junction components Guide to selecting PN junction components K.117 Primary protector parameters for the surge protection of equipment Ethernet ports This recommendation should be used for the harmonization of existing or future specifications issued by manufacturers K.118 Requirements for lightning protection of fiber to the distribution point equipment Provides the information to protect the equipment in customer premises implementing gigabit broadband access technology that exploits the original wire pairs from plain old telephone service (POTS) services