IEEE C62.55-2020 pdf free download.The title is IEEE Guide for Surge Protection of DC Power Feeds to Remote Radio Heads.
The waveform of currents likely to exist on dc feeds to equipment located at the tops of towers due to a lightning strike, and the consequences of that waveform for protector design, are described in this guide.
Keywords: EEE C62.55,lightning powering feed, protection, remote radio head, RRh, SPD,surge protective device, surge waveform, towers.
This revision of IEEE Std C62.55-2017 includes the corrections indicated in IEEE Std C62.55-2017/Cor 1-2018,and updating the clause on multiple strokes and continuing current. It also includes updates to the original 2017 version.
1. Overview
This guide begins by discussing the characteristics of lightning flashes having a single stroke that might strike a tower. The nature of the resulting current on the de feed is then discussed. Next, consideration is given to lightning flashes having multiple strokes. Finally, guidance on selecting a surge protective device (SPD) for the dc feed and practical considerations are discussed.
1.1 Scope
This guide covers the application of SPDs used to protect the dc power feeds of remote radio heads (RRHs) and power supplies of optical fiber cable systems feeding the antenna systems.
1.2 Word usage
The word ha indicates mandatory requirements strictly to be followed in order to conform to the standard and from which no deviation is permitted( hal equals is required to).
7. The surge on a dc feed
Towers, regardless of height, are likely to be struck by lightning. which will cause a surge on the RRTI power feed. Because of that, surge protection is needed. What will this protection have to deal with? Two use cases illustrate the issue. The details of these cases can be found in Zafiris [B30] and Xiong [B28].In both cases. a simulated tower and metal-oxide varistor (MOV) protection were set up in a lab, for example as in Figure 3. or Figure 3, the simulated tower consisted of square steel tubes bent in a U shape to reduce the length of the generator leads, and the feed wire was protected with MOVs at each end.