OPGW Over-Pulley Test
The pulley test is conducted to verify that OPGW will not be damaged or have its performance characteristics degraded when sliding over pulleys of the recommended dimensions. This test shall be performed in accordance with DL/T 832-2016.
A typical pulley test setup is shown in Figure 1. The test sample is secured at both ends using appropriate cable clamps. A light source and optical power meter are installed at opposite ends of the fiber under test to measure fiber loss. Prior to testing, the starting point, midpoint, and endpoint of the test section must be clearly marked. After testing, measure the ellipticity of the optical cable and its components, comparing it with the maximum allowable oxygen content (MAOC) at the corresponding marked locations.
① Install the OPGW sample on pulley equipment. The test optical cable length shall be no less than 100 m, with the section between tension clamp installation points no less than 5 m. Fusion splice the optical fibers into a single loop to measure fiber attenuation.
② Pass the cable through pulleys with a diameter no less than 40 times that of the cable. Pull the cable forward and backward 10 times each, applying a tensile force of 15% RTS. The pulling distance is 2 m, with an envelope angle of 30℃.
③ When the cable passes through the pulley for the 1st and 10th time, measure the cable diameter at the start, midpoint, and end of the pulled section using a micrometer. After testing, strip the outer strand and measure the diameter of the optical unit tube at the marked positions.
① After testing, the loss of the tested fiber at 1550 nm wavelength shall not exceed 0.01 dB/km. Any permanent loss increase exceeding the specified value shall be considered a test failure.
② The ovality of the optical unit shall not exceed 10% of its MAOC.
③ The tested OPGW shall show no damage.