FTTH test

light source and optical power meter as a basic instrument enter a period of fiber optic cable construction of FTTH, should be based on the actual need to make a selection from the functionality and performance, general requirement is: the & # 1048715; Has the LCD display of light. The & # 1048715; Emission light power tunable light source. The & # 1048715; Which has the function of the modulation wave light source and optical power meter. The & # 1048715; Can directly read the depletion of the optical power meter. After entering a period of FTTH cable laying, to ensure that this optical fiber ( Including optical fiber mechanical connection connection plug) Attenuation value is less than 1. 5 db, must to test it. At present, the commonly used based on PON FTTH light power measuring instruments are mainly ordinary optical power meter and power meter two wavelength separation PON. Ordinary optical power meter, wavelength separation PON power meter, every time the ordinary optical power meter can only measure the wavelength, the wavelength separation PON power meter to measure the power of each wavelength at the same time, and in order to provide each wavelength by, the alarm or not by state power threshold can be set product performance requirements and test operation due to the light source and optical power meter is usually used when using so attention should be given to the consistency of the parameter Settings. Specific to test 1310 nm wavelength attenuation upward direction, downward direction to test the 1490 nm wavelength attenuation, when need to provide CATV business, the downside of testing may be increased to 1550 nm wavelength attenuation and reflection attenuation, operation steps are as follows: the first step: set the benchmark ( Reference) Values (1) open the optical power meter, select the working wavelength. (2) open source, choose the correct wavelength and makes it stable. (3) with a light jump fiber connection light source and optical power meter. Note: the use of light jump fiber must be same as the measured enter a fiber optic cable used by optical fiber. (4) optical power meter measured light power value at this time. Note: at this time of light power values should be similar to the setpoint of illuminant itself, if have larger deviation carefully clean light jump fiber connection plug jump fiber end face or directly replace the light. (5) according to the optical power meter 'zero' key this time the dB power meter readings of 000 measured optical power value is set to become the benchmark ( Reference) Value. Note: the optical power meter to zero after the dB reading digits after the decimal point will have slightly change, this is normal phenomenon. Step 2: enter a period of optical fiber attenuation value measurement (1) the light source and optical power meter, respectively, with the door at the ends of the cable optical fiber mechanical connection plug is connected. Note: need to clean optical fiber mechanical connection plug end face. (2) readings of the optical power meter dB, this time power meter displays the dB reading is enter a section of the cable under test ( Including optical fiber mechanical connection connection plug) The attenuation values. Note: the optical power meter readings shall show that in the dB should be not installed in dBm. Household and ONU installation, after opening the cable laying, wavelength separation PON power meter can be used for ODN link to the downstream and upstream attenuation test, it can work under way through signals, operational steps such as: separate the wavelength PON power meter, respectively, and enter a period of optical fiber cable and connect the ONU equipment jump optical fiber connected at this time of 1310 nm, wavelength values for ONU to wavelength separation under PON optical link loss between the power meter; 1490 wavelengths values for OLT to wavelength 1490 nm separation between PON power meter fiber optic link loss. Using wavelength separation of PON optical power meter measurement, has the following functions: the & # 1048715; Measurement can be directly connected to the network, does not affect the ascending and descending of optical signal transmission. Can measure the power of all wavelengths at the same time. Can detect the sudden power of the light signal. Fault diagnosis can be inserted into the network at any point.