Direct-current (dc) ice-melting conditions, melting current, melting duration, and the amplitude of harmonics injected into the power grid are specified in this guide to support the safety, efficiency, and effectiveness of dc ice melting. The technical parameters, inspection, operation, and maintenance of dc ice-melting devices are also specified. The purpose of this guide is to provide dc ice-melting methods, which can be used to help prevent collapse of power transmission towers as well as disconnection and outage of transmission lines under continuous snow and freezing rain.

The guide specifies the direct-current (dc) ice-melting conditions, melting current, melting duration, and the amplitude of harmonics injected into the power grid to support the safety, efficiency, and effectiveness of dc ice melting. It also specifies the technical parameters, inspection, operation, and maintenance (O&M) of dc ice-melting devices. The guide is applicable to dc ice melting of 110 kV to 500 kV ac/dc overhead transmission lines.

The purpose of this guide is to provide dc ice-melting methods that can be used to help prevent collapse of power transmission towers as well as disconnection and outage of transmission lines under continuous snow and freezing rain.