Testing Procedures

Fiber Optic Cable Testing OTDR Testing Procedure

Test Fiber Optic Cable shall include Optical Time Domain Reflectometer (OTDR) tests, Coarse Wave Division Multiplexor (CWDM) OTDR tests, spectrum analysis of CWDM fiber, and optical power meter tests of all installed fiber and modified existing fiber on the project.

The Developer shall use equipment that is calibrated annually. A copy of the most recent certificate of calibration and all out-of-tolerance conditions shall be provided to the Department prior to the initiation of testing activities. The following equipment and information is required to perform fiber optic cable tests:

• An OTDR (submit certification to the Department)
• A Coarse Wave Division Multiplexor OTDR (submit certification to the Department)
• An optical spectrum analyzer (submit certification to the Department)
• Optical Power Meter Equipment capable of measuring optical power in dBm (submit certification to the Department)
• A launch box (min length – 1000 feet)
• A light source at the appropriate wavelength
• Test jumpers shall be 3 feet to 12 feet long with connectors that are compatible with the light source and power meter and shall have the same fiber construction as the link segment being tested.

Prior to splicing and testing on the project the Developer shall submit a detailed Method Statement to the Department describing the splicing and testing plan and schedule.  Discussion of the Developer’s Device Cutover Plan and a proposed Device Cutover Schedule shall be included in the Method Statement.  No fiber optic splicing shall begin until the Method Statement is submitted and approved.  If at any time it is determined that work began without an approved Method Statement, or the work is not following the approved Method Statement, an immediate “stop work” order will be issued and work will not resume until the Method Statement has been submitted and approved.  Once the splicing and testing begins, the Method Statement shall be updated if necessary to address any changes in the original planned and approved procedures.

The Developer shall conduct fiber optic testing at the following stages:

• Pre-installation testing – bi-directional OTDR test of every fiber on every reel after delivery of the reel
• Post installation and pre-splicing test – bi-directional OTDR test of every fiber of every cable after fiber is installed in the ground
• Post-splicing tests, pre-CWDM filter splicing tests

1. 1. Optical Power meter test from all fiber terminated in communications cabinets to a network facility for all fiber that is not used for CWDM on the project.
   2. Bi-directional OTDR test of all fiber between termination point in a network facility and cable end and between termination point in a network facility and communications cabinets for fiber that is not used for CWDM on the project
   3. Bi-directional CWDM OTDR test of all fiber between termination point in a network facility and cable end and between termination point in a network facility and communications cabinets for all fiber that is used for CWDM on the project.

• Post-CWDM filter splicing tests

1. 1. Spectrum analysis of all terminated fiber used for CWDM after filters have been spliced
   2. CWDM-OTDR
   3. Optical Power meter test and documented attenuator values

• Re-testing of all stages above if initial test fails and after corrective action is taken

The guidelines for fiber optic cable testing include:

Launch box and test jumpers must be of the same fiber core size and connector type as the cable system: Single mode fiber 9.0mm (nominal) /125 mm

• The light source and OTDR must operate within the range of 1310±10 nm and 1550±20 nm single mode nominal wavelength for testing in accordance with Telecommunications Industry Association (TIA) TIA-526-7 Measurement of Optical Power Loss of Installed Single-Mode Fiber Cable Plant.
• The power meter and the light source must be set to the same wavelength during testing.
• The OTDR and power meter must be calibrated at each of the nominal test wavelengths and traceable to the National Institute for Standards and Technology (NIST) calibration standards.
• The calibration of the OTDR and power meter shall conform to the requirements set forth in Telecommunications Industry Association/Electronic Industries Alliance (TIA/EIA) TIA/EIA-455-226 Calibration of Optical Time-Domain Reflectometers and TIA-455-231 Calibration of Fiber Optic Power Meters, respectively

The Developer shall document jacket length measurements for lateral and backbone cable at each end including splice enclosures and patch panels, and at any intermediate splice points.

The Developer shall document bare fiber slack not accounted for in jacket length.

All system connectors, adapters and jumpers shall be cleaned per manufacturer’s instructions before measurements are taken.

At locations of new lateral fiber optic cable installation and at locations that require the re-installation of existing lateral fiber optic cable, the Developer shall conduct testing from the termination panel mounted in the communications cabinet to the splicing manhole. The bi-directional test shall be conducted from the termination panel towards the splicing manhole and from the splicing manhole to the communications cabinet termination panel.

Final splicing will not begin until such time that the Developer submits OTDR test results to the Department and a representative of the Department reviews the results.

Final OTDR testing from the communications cabinet to the corresponding node building shall be conducted after their splicing work has been completed.  All issues with communications

related to Developer installation and workmanship shall be remediated by the Developer at no additional cost to the project.

A functional test shall be made in which it is shown that each and every part of the system functions as specified or intended herein.

a. Optical Fiber Cable Testing with OTDR

The Developer shall perform an OTDR test of all fibers in all tubes on the reel prior to installation of the fiber. The test results shall be supplied to the Department prior to installation of the cable.

Fiber testing shall be performed on all terminated fibers from patch panel to patch panel and unterminated fibers from end to end. Additionally, mid entry splices into mainline cables require testing of all strands in the mainline cable before and after installation. Testing shall consist of a bi-directional end-to-end OTDR trace.

Loss numbers for the installed link shall be calculated by taking the sum of the bi-directional measurements and dividing that sum by two.

The Developer shall use an OTDR that is capable of storing traces electronically and shall save each final trace.

The Developer shall use a test reel of minimum length identified in the Materials section of this Special Provision. The Developer shall indicate the length of the test reel, in feet, for all test results.

If the fiber designation is not indicated on the trace itself, the Developer shall provide a cross-reference table between the stored trace file name and the fiber designation.

The Developer shall record the following information during the test procedure:

• Name and contact information of person conducting the test
• Type of test equipment used (manufacturer, model, serial number, calibration date and valid certification of calibration)
• Date test is being performed
• Optical source wavelength and spectral width
• Fiber identification
• Start and end point locations
• Test direction
• Launch conditions
• Method of calculation for the attenuation or attenuation coefficient
• Acceptable link attenuation
• Cable manufacturer stated index of refraction for cable being tested
• Jacket readings in and out of each splice vault and each pull box

b. Optical Fiber Cable Testing with Optical Power Meter

The Developer shall conduct an Optical Power Meter Test of each fiber installed.

Single mode segments shall be tested in one direction at both the 1310 nm and 1550 nm wavelength.

The following information shall be recorded during the test procedure:

• Names of personnel conducting the test
• Type of test equipment used (manufacturer, model, serial number, calibration date and a valid certification of calibration)
• Date test is being performed
• Optical source wavelength and spectral width
• Fiber identification
• Start and end point locations
• Test direction
• Reference power measurement (when not using a power meter with a Relative Power Measurement Mode)
• Measured attenuation of the link segment
• Acceptable link attenuation

c. Acceptable Attenuation Values

The Developer shall calculate acceptable attenuation values for each fiber tested. These values represent the maximum acceptable test values.

The general attenuation equation for all single mode link segments is as follows:

Acceptable Link Attenuation = Cable Attenuation + Connector Attenuation + Splice Attenuation.

8.3 mm (nominal) Single-mode Attenuation Coefficients:

• Cable Attenuation=Cable Length (km) x (0.35 dB/km at1310 nm and 0.22 dB/km at1550 nm)
• (No. of Mated Connections x 0.50 dB)
• Splice Attenuation = Splices x 0.30 dB

d. Test Procedures

The single mode Optical Power Meter fiber test shall be conducted in accordance with TIA-526-7.

The single mode OTDR test shall be conducted in accordance with TIA-526-7.

Testing for CWDM single wavelength filters (CWDM filter) shall be conducted in the following manner to ensure that the filter Pass, Reflect and Common pigtails are spliced to proper lateral

fiber strands.  Testing procedures and CWDM data flow information is included on the plans. Testing shall be conducted for all CWDM wavelengths applicable to each fiber strand used for data communications.  CWDM wavelengths on this project are expressed in nanometer (nm) and include 1430 nm, 1450 nm, 1470 nm, 1490 nm, 1510 nm, 1530 nm, 1570 nm, 1590 nm, and 1610 nm. Industry standard wavelengths (e.g. 1430 nm = 1431 nm) shall be observed.

After completion of fiber optic cable installation and prior to the CWDM filter splicing, all backbone cable to lateral cable splices shall be completed in the individual Ethernet switch sub-rings.   Required steps shall include:

• The backbone end of Lateral Cable 1 shall be spliced to the fiber optic backbone cable in Splice Closure 1. Once this splice is complete no future access to Splice Closure 1 shall be made unless a re-splice is required.
• The opposite end of Lateral Cable 1 shall be spliced to itself in Splice Closure 2 in a manner to achieve continuity in the backbone strands from the beginning of the sub-ring (first node building) to the far end of the sub-ring (next node building).
• An OTDR test shall be conducted on the sub-ring from building to building to ensure proper splicing of Lateral Cable 1 in Splice Closure 1.

Once the OTDR test is complete the results shall be submitted to the Department for approval.  After approval the splicing of CWDM filters in Splice Closure 2 may begin.

The Developer shall be required to break the Lateral Cable 1 splices in Splice Closure 2 used in the continuity test and conduct the CWDM filter splicing per the project fiber splice plans.  This will include splicing of Lateral Cable 1 and Lateral Cable 2 in Splice Closure 2 and the termination of Lateral Cable 2 in the communications cabinet.

After CWDM filter splicing, the Developer may use one of the following methods to ensure the proper CWDM filter splicing.

• By using a fiber identifier, testing of the incoming signal from either the upstream or downstream CWDM location, the Developer shall show the Department that proper CWDM filter pigtail splicing has been achieved.
• By using a spectrum analyzer to test the incoming wavelength to ensure proper splicing and wavelength of the CWDM signal.

Once all splicing of the individual sub-ring is complete the Developer shall conduct the CWDM-OTDR and spectrum analyzer testing and submit the results to the Department.  At the acceptance of these tests, the Developer shall determine the proper optical attenuator to install in the Receive (RX) ports at both the communications termination panel and the node building termination panel.  After installation one final test of optical power shall be conducted to determine if the proper signal strength is being achieved by the Ethernet switch CWDM optic.

At that point the Colorado Department of Transportation, Colorado Transportation Management Center personnel along with Ciena network engineers will configure the sub-ring into the overall CDOT ITS network.  If network communications cannot be achieved, a review of the CWDM testing materials will begin.

e. Test Acceptance

The Developer shall demonstrate that the tests result in acceptable attenuation values.

The Developer, solely at the Developer’s expense, shall re-splice all fusion splices and re-terminate all terminations that have test results exceeding acceptable attenuation values. The Developer, solely at the Developer’s expense, shall retest all fiber links that have been re-spliced and shall retest all fiber links that have been re-terminated.

The Developer, solely at the Developer’s expense, shall bring all links not meeting the requirements of this specification into compliance.

f. Submittals

The Developer shall submit test result documentation as both a hard copy and electronic copy.

After each reel test, the Developer shall submit one hard copy of the OTDR trace for every fiber on the reel.

After installation, the Developer shall submit two hard copies and one electronic copy of the following tests:

• Continuity OTDR trace for every spliced fiber which the CWDM optical network will utilize.
• OTDR trace for every fiber the high speed DWDM optical network will utilize.
• CWDM-OTDR trace for every fiber which the CWDM optical network will utilize.
• Spectrum analyzer test results for every fiber which the CWDM optical network will utilize.
• OTDR traces and power meter results for all “dark” unused fiber strands in the backbone fiber optic cable from node buildings.

Hard copy traces shall be organized and bound in logical order in an 8 ½ inch x 11 inch hard cover binder.

The Developer shall submit, after approval of the hard copy traces, electronic copies of all traces (PDF and native file format) and appropriate software, if needed, to allow reading the traces.

The Developer shall submit one copy of the complete contract Plans, including additional drawings issued as part of all change orders, with all deviations clearly marked in color. Deviations to be noted shall include at a minimum, but not be limited to, the following:

• Fiber Splice location
• Fiber Splice configuration
• Termination layout

After all splicing and fiber optic testing is completed the Developer shall test the optical power of the incoming, (Receive) signal at each field Ethernet switch and existing node building location. To obtain the most accurate values of optical power, the testing equipment shall be attached to the SFP optic end of the pre-connectorized patch cable.

Once the optical power has been tested, the Developer shall install the appropriate attenuator in the receive port to meet the receive values of the SFP optic module, including a design margin of 6 dB (to allow for degradation over the life of the system).