SR Ring & Counterweight
SR (Snow-Resistant) Rings and Counterweights are both countermeasures for preventing heavy snow accretion on overhead lines. (Fig.1)
The combination of the two have been widely used for many years in Japan as a standard countermeasure against snow accretion.
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SR Ring
Facilitates drop-off of accreted snow
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Features
SR Rings are a countermeasure for reducing the amount of snow accretion.
Attaching these rings onto a stranded wire at a certain interval facilitates the drop-off of lumps of wet snow by preventing lumps from sliding spirally around the strands.
Counterweight
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Features
Counterweights are installed to prevent snow accretion.
Wet snow tends to accrete heavily by twisting the wire. In contrast to this phenomenon, installing counterweights can strengthen the torsional stiffness of the wire and reduce the snow accretion.