Strange Devices on Transmission Lines: 5 Little-Known Practical Functions（1）

1 Aviation Warning Spheres
Aviation warning spheres, also known as reflective safety spheres, are used on overhead transmission lines near airports, especially on extra-high-voltage (above 220kV) lines and river-crossing transmission lines. Highly visible aviation marker spheres (aviation warning spheres) must be installed along the lines to provide warning signals.
The aviation marker sphere (aviation warning sphere) has a diameter of ф=600mm. The sphere can be manufactured in various bright colors, including all-white, all-orange, all-red, orange-white dual-color, or orange-red dual-color. The sphere is made of reinforced engineering plastic. The clamp connecting the aviation warning sphere to the high-voltage cable is made of cast aluminum, and fasteners are made of stainless steel. The sphere weighs approximately 15kg.

Installation Method:

• Install the marker sphere (aviation warning sphere) on the steel cable of the lightning protection ground wire on overhead towers. The spacing between each marker sphere must not exceed 30 meters and should be evenly distributed.

• The marker spheres (aviation warning spheres) are available in white and orange; they should be installed alternately.

• In cases involving multiple wires or cables, the marker sphere (aviation warning sphere) should be installed at a height not lower than the highest marked overhead line.

2 Bird Deterrent Devices – Bird Spikes
Bird spike devices are typically installed above suspension insulator strings and jumper strings. Considering safety distances, for vertically arranged conductors, bird spikes are generally installed only on the upper crossarm. For horizontally arranged conductors, bird spikes should be installed on each phase.
Disadvantage of this method: After prolonged use, birds gradually adapt to the bird spikes, and their effectiveness in deterring birds diminishes over time.

3 Vibration Monitoring Device
A vibration monitoring device measures the aeolian vibration of overhead line conductors and ground wires.
It includes a displacement sensor, an anemometer, and a temperature sensor.

4 Distributed Fault Location Device
A distributed fault location device performs waveform analysis of line faults to achieve fault location and preliminary cause analysis, enabling operation and maintenance personnel to locate fault points more quickly.

5 Ice Accretion Online Monitoring Device
The ice accretion online monitoring device is powered by solar energy combined with a high-capacity battery pack, providing continuous power for real-time monitoring of line icing conditions. The device’s high-definition camera unit, weather sensors, and inclinometer sensors continuously monitor data such as insulator string tension, inclination angle, temperature, humidity, wind speed, wind direction, and visual imagery. This data on ice conditions on overhead lines is transmitted in real time to a monitoring platform via 4G/WiFi/fiber/Lora communication channels, enabling monitoring personnel to manage icing conditions on the power grid. With support for multiple selectable communication channels, the device overcomes data transmission challenges in remote areas.