Warning sphere is used for warning aircraft pilots in daytime and nighttime, which is compliant with International Civil Aviation Organization (ICAO) recommendations annex 14 chapter 6. It can be used in overhead cable, guyed wire, especially in extra high voltage power transmission line, cross river power transmission line, cross road, bridge power transmission line and so on. It is made of high-grade polyethylene with the color of red, orange, white. Different colors' warning sphere should be displayed alternately. If there are many lines, warning sphere should be displayed on the highest line. It can resistant to corrosion, rust, water, dust, high temperature, can be used for long time.

Warning sphere specification

• Sphere body material: high-grade polyethylene.
• Color: aviation red, aviation orange, aviation white.
• Sphere diameter: 200 mm, 300 mm, 340 mm, 400 mm, 600 mm.
• Thickness: 8 mm.
• Weight: 2-4 kg.
• Visible distance: 1250 m from the air and 350 m from the ground.
• Voltage range: < 150 KV.
• Conductor diameter: 6-26.5 mm.
• Reflective strip: optional.
• Preformed armor rods: optional.
• Warranty: 2 years.
• Packaged in carbon box or wooden box.

Standard

• ICAO Annex 14, 6th Edition, July 2013. Annex 14 to the Convention on International Civil Aviation.
• FAA AC 70/7460-1L, obstruction Marking and Lighting.
  • Date Issued: December 04, 2015.
  • Responsible Office: AJV-1, Airspace Service.
  • Description: This Advisory Circular (AC) sets forth standards for marking and lighting obstructions that have been deemed to be a hazard to navigable airspace.

WS-1: Orange warning sphere.

WS-2: Red warning sphere.

WS-3: White warning sphere.

WS-4: An orange warning sphere is bundled on power line.

WS-5: Upper slot of red warning sphere.

WS-6: Lower slot of red warning sphere.

WS-7: Warning sphere in all angles.

WS-8: Warning sphere on power line conductor in all angles.

Features of warning sphere

• Resistant to corrosion, rust, water, dust, high temperature.
• Not have metal annex, good integrity, high strength.
• Light, not have influence for power line.
• Self thickness, smooth appearance, fresh color.
• Properties do not change under various complex environment, such as rain, snow, ice, oil and so on.
• Warning sphere can suit power line conductor which diameter is between 6 mm and 26.5 mm.
• Optional preformed armor rods for fixing warning sphere on power line.
• Reflective tape can make pilots see power line clearly.
• Easy to install.
• Long service life.

Application of warning sphere 
Our polyethylene warning spheres are used in overhead cable, guyed wire, supporting tower, especially in super high voltage power transmission line, cross river power transmission line, cross road, bridge power transmission line and so on.

Installation: Five steps for warning sphere installation.

1. The warning sphere has two slots. Upper slot facing sky is used for fixing the preformed armor rods. Lower slot facing ground is used for attaching the conductor. (300 mm diameter warning sphere as example)

2. Apply part of armor rods to conductor, make sure wrapping armor rods with the same direction as conductor twisted.

3. Place the warning sphere on the conductor, then apply armor rods on the upper slot.

4. Wrap the rest of armor rods to conductor.

5. Warning sphere is installed on conductor.

Warning sphere installation note

• The spacing between two consecutive warning spheres or between a warning sphere and a supporting tower should be appropriate to the diameter of the warning sphere. The maximum spacing is 30 m with sphere's diameter is 600 mm.
• If multiple wires or cables are involved, warning sphere should be located in the highest wire.
• When installed, different colors' warning spheres should be displayed alternately. The color selected should contrast with the background to ensure marker balls will be seen clearly.
• Warning spheres should alternate aviation orange, white, yellow, with aviation orange markers positioned at each end.
• If less than four markers are on the line, all markers should be aviation orange.

Contact us immediately if you are interested in our warning sphere. And you can contact us via sales@warningspheres.com  if you have any questions.