C22.3 NO. 5.1-93 (R2017)

Specifies the principles and general practices of electrical protection applicable to overhead supply systems operating at more than 750 V but less than 50 kV phase to phase and communication systems, where the lines of those systems are located so that inadvertent electric contact between them could occur, resulting in a contact voltage not exceeding a limit agreed to by the communication and supply companies.

Preface 1.1 This Standard outlines the principles and general practices of electrical protection applicable to overhead supply systems operating at more than 750 V but less than 50 kV phase to phase and communications systems, where the lines of those systems are located so that inadvertent electric contact between them could occur, resulting in a contact voltage not exceeding a limit agreed to by the communication and supply companies. 1.2 This Standard applies to overhead supply and communications systems that meet the requirements of CSA Standard CAN/CSA-C22.3 No. 1 where coordinated electrical protection is specified. 1.3 The following effects are within the scope of other Standards and therefore are excluded from this Standard: (a) the effects on communications conductors entering power stations or passing through the zone of influence of that station\'s ground potential rise (GPR); (b) the effects of faults other than single phase-to-ground faults; and (c) the effects of longitudinal induction and ground potential rise that result from normal operating or fault conditions.