Draft Guide for the Application of Low-Voltage (1000 Volts rms or Less) Surge Protective Devices Used on Secondary Distribution Systems (Between the Transformer Low-Voltage Terminals and the Line Side of the Service Equipment)
This guide encompasses the application of surge protective devices (secondary arresters) from thesecondary terminals of the distribution transformer to the line side of the service equipment NOTE??For reference@ Figure 1 shows that the location covered by this guide is within Category C (from C62.41.1?-2002@ see Normative references). The service entrance equipment includes all terminals and busses in the enclosure@and connection made to those terminals or busses with conductors other than load-carrying conductors. SurgeProtective Devices limit transient [surge] overvoltages by diverting surge currents .SPD coordination considers thepower system characteristics@ the equipment to be protected and the location of the Surge Protective Devices. ThisApplication Guide also provides an Informative Annex that presents information on risk factors Purpose The purpose of this guide is to address many of the aspects to be considered when applying surgeprotective devices from between the secondary terminals of the distribution transformer toand the line sideof the service equipment.