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Section 2. Sewerage of electricity
Overhead power lines with voltage above 1 kV. Passage of overhead lines on bridges
Encyclopedia of radio electronics and electrical engineering / Rules for the installation of electrical installations (PUE)
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2.5.273. Laying of overhead lines of 1 kV and above on all bridges, as a rule, is not allowed.
If there is a justified need, it is allowed to pass overhead lines along bridges made of non-combustible materials, while the supports or supporting devices limiting spans from the shore to the bridge and through the draw part of the bridge must be anchors of a normal design, all other supporting devices on bridges can be of an intermediate type, on these devices with supporting strings of insulators, the wires must be suspended in blind clamps. The use of pin insulators is not allowed, except for VLZ, where their use is allowed with the fastening of wires with spiral spring bindings.
2.5.274. On metal railway bridges with a ride on the bottom, equipped with upper ties throughout, wires can be placed directly above the bridge span above the ties or outside it; it is not allowed to place wires within the limits of the proximity of buildings, as well as within the width occupied by the elements of the contact network of electrified railways. Distances from overhead lines to all MPS lines laid along the bridge structure are taken according to 2.5.251, as for cramped sections of the route.
On urban and highway bridges, wires may be located both outside the span and within the width of the pedestrian and carriageway of the bridge.
On guarded bridges, it is allowed to place overhead lines below the level of the pedestrian part.
2.5.275. The smallest distances from overhead lines to various parts of bridges should be taken in accordance with the requirements of the organizations in charge of this bridge. In this case, the determination of the largest wire sag is made by comparing the sag at the highest air temperature and with ice.
 See other articles Section Rules for the installation of electrical installations (PUE).
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