STANDARD TEST PROCEDURE PRE-TEST QUALITY OF OPTIC FIBRE CABLE ON DRUMS TYPE OF CABLE :

Transcription

1 PROCEDURE PRE-TEST QUALITY OF OPTIC FIBRE CABLE ON DRUMS STANDARD TEST PROCEDURE PRE-TEST QUALITY OF OPTIC FIBRE CABLE ON DRUMS TYPE OF CABLE : 1) SINGLE MODE 2) MULTI-MODE IN EXCESS OF 100 METRES PRC JANUARY 2008 Revision 2.00 NON-DISCLOSURE OF INFORMATION Information contained in this document is proprietary in nature and/or protected by copyright. Please obtain written permission from the Author prior to reproducing this document, in whole or in part. Author : BG Nel Page 1 of 10

2 TABLE OF CONTENTS I DOCUMENT AUTHORISATION...3 II DISTRIBUTION...3 III DOCUMENT CHANGE HISTORY...3 IV CHANGES SINCE LAST REVISION...3 V ABBREVIATIONS, ACRONYMS AND DEFINITIONS...4 VI RELEVANT DOCUMENTATION OFC OTDR TEST SEQUENCE PROCESS FOR PRE-TESTING AND ACCEPTANCE OF OFC DRUMS GENERAL Background Personnel Instruments and Optical Safe Working Guidelines Tests to be done TESTING PROCEDURE Verify metre marks on the cable sheath Verify info on cable sheath in accordance to contract Measure diameter of cable Clean cable ends Connect OTDR on cable Splice fibres on both ends Acquire profiles Recording splice losses (Attenuation profile / trace of splice losses) GUIDELINES FOR TESTING OPTICAL FIBRE CABLE ON DRUMS OTDR settings Presenting OTDR Test Results (Traces)...9 Author : BG Nel Page 2 of 10

3 I DOCUMENT AUTHORISATION FUNCTION NAME TITLE & DIVISION SIGNATURE DATE Compiled by : BG Nel Technologist, Quality Assurance Reviewed by : F Nel Head of Department (Projects Execution) Authorised by : M Nuttall Divisional Manager, Transmission Services II III DISTRIBUTION Once updated, a copy of the latest revision will be published in the document management system in use. to this effect will be sent to the relevant personnel or heads of department. DOCUMENT CHANGE HISTORY ISSUE NO. DATE ISSUED ISSUED BY HISTORY DESCRIPTION 1.00 June 2001 Transmission New document 2.00 January 2008 Transmission Converted to ISO standard IV CHANGES SINCE LAST REVISION CLAUSE All Converted to ISO standard DESCRIPTION Author : BG Nel Page 3 of 10

4 V ABBREVIATIONS, ACRONYMS AND DEFINITIONS ABBREVIATIONS AND ACRONYMS APC OF OFC OTDR QAD Angle Polished Connector Optical Fibre Optical Fibre Cable Optical Time Domain Reflectometer Quality Assurance Department DESCRIPTION DEFINITIONS None DESCRIPTION VI RELEVANT DOCUMENTATION APPLICABLE DOCUMENT NO. None DESCRIPTION LOCATION RELEVANT DOCUMENT NO. None DESCRIPTION LOCATION Author : BG Nel Page 4 of 10

5 1. OFC OTDR TEST SEQUENCE SEQUENCE TESTING OFFICER OTDR TEST RESULTS 1) Factory Testing Supplier a) Hardcopy with drums b) to Project Manager c) to QAD 2) Pre-testing Drum's Standard Test Procedure 3) Post-installation Standard Test Procedure Project Services Project Services to QAD to QAD 2. PROCESS FOR PRE-TESTING AND ACCEPTANCE OF OFC DRUMS Start Project Services will conduct test on drums. Test results will then be ed to Quality Assurance Department (QAD) QAD will analyse the results and compile a Report. 2 1 The progress status will be presented to Project Services and Services Operations Program Manager will rectify problem and retest or notify OFC supplier and contractor for corrective action NO QAD will the Report to the Program Manager. Corrective action Fibres Acceptable? YES Author : BG Nel Page 5 of 10

6 3. GENERAL 3.1 Background Optical quality tests on Optical Fibre Cable must be conducted after delivery from the manufacturer. This test procedure must be carried out on Optical Fibre Cable when it is still on the drums These tests will be conducted on request of the specific Project Manager who ordered the cable or on request of the Head of Quality Assurance Transmission. If there are any abnormal indicators in the results of such tests the cable will be returned to the suppliers The OTDR results of the tests of the first drum must be submitted to the Quality Assurance Transmission in a report format. This submission must be submitted within forty-eighty (48) hours after testing the first drum. 3.2 Personnel Personnel responsible for the execution of the tests must have the following minimum requirements : A course in Optical Fibre Cable Personnel under training and non-permanent staff members can only conduct tests under the supervision of trained personnel Transport Telecoms specifications concerning Optical Fibre Cable. (Obtain specifications used in the contract documentation from Project Manager.) 3.3 Instruments and Optical Safe Working Guidelines Vehicle suitable for terrain Fusion Splicer compliant with Transnet Freight Rail specifications Cleaning kit which includes the following : Vernier Optical Time Domain Reflectometer (OTDR) with an E2000 APC connector Pigtail with E2000 APC connector to fit OTDR. Author : BG Nel Page 6 of 10

7 3.3.4 Contract documentation. 3.4 Tests to be done With reference to Transnet Freight Rail's specifications SPC and SPC the following tests must be done : 4. TESTING PROCEDURE Record the meter marks on the cable sheath Verify information on cable sheath in accordance to contract Measure diameter of cable Splice fibres in cable at both ends in tandem (cascade) fashion (On single mode fibres). Take OTDR profiles at 1550 nm only at both ends (On multimode fibres). Testing cable length of greater than 1000 m may be done with a power source and power meter at 850 nm Measure the loss of each splice. 4.1 Verify metre marks on the cable sheath The metre marks, cable length of the inner three (3) metre test tail must be visible on the drum. The marks on the outer end of the cable must be subtracted from the inner. This reading must be compared with the optical readings (OTDR). 4.2 Verify info on cable sheath in accordance to contract Ensure the format of information displayed on the cable sheath is in compliance with the contract specifications. 4.3 Measure diameter of cable Use the vernier to take three measurements of the cable diameter. The position of measurements on the cable must be more than one meter apart. 4.4 Clean cable ends Strip off the sheath of the cable at the inner and the outer ends of the drum to access the bare fibres. The bare fibre ends must be approximately one metre in length. Author : BG Nel Page 7 of 10

8 4.4.2 Clean the cable with a rough piece of paper. Use the small cleaning cloths only for cleaning the fibre when splicing During the stripping process ensure that the cable is laid out as per inspection. (Physical composition of cable layers). 4.5 Connect OTDR on cable Connect the pigtail on the OTDR Cleave the other end of the pigtail Inspect the cleave by using the splicer's display (this will ensure a low insertion loss into the fibre-under-test) Connect pigtail to fibre No. one on the drum. 4.6 Splice fibres on both ends Cleave the outer end of fibre on the drum Use the fusion splicer to splice all fibres on the drum in tandem (cascade) Log each splice with the OTDR that is connected to fibre one Using the OTDR, ensure a splice loss of smaller than 0,1 db (for single mode). This must be achieved for at least 70% of the splices, 30% of the splices must be zero db (this includes gainers) If the splice loss is greater than 0,1 db, break the splice and redo it. Log the third attempt if splice loss is greater than 0,3 db. The drum must be returned to supplier When more than one attempt is achieved for a good splice loss, it must be noted in the report. 4.7 Acquire profiles Inspect the quality of the splice by using the splicer's display Splice the pigtail onto the last fibre of the drum Use the OTDR to acquire profiles of the fibres Ensure that the reflectance value at the insertion point of the OTDR into the cable exceeds the value stated in the guidelines. Author : BG Nel Page 8 of 10

9 4.7.5 OTDR trace files shall be stored in NATIVE format Acquire a profile from the inner and outer end of the cable drum at 1550 nm. (Only for single mode) Save all profiles on storage device in the OTDR Use the cable number for the OTDR trace file name. 4.8 Recording splice losses (Attenuation profile / trace of splice losses) Use the OTDR to measure each splice loss Compare the loss measured in both directions on each splice to confirm any fibre core deviations. 5. GUIDELINES FOR TESTING OPTICAL FIBRE CABLE ON DRUMS 5.1 OTDR settings Range setting : The appropriate range setting must be used. (Do not set the OTDR to an 80 km range when measuring 20 km OFC section.) Pulse width : Switch the OTDR to measurement at the shortest pulse width. (Analysing the end of the OFC-trace must be possible.) Time duration : For the best results the maximum average time must be set. This can only be achieving by testing the OF for a longer time. Readings should not be less then 60 seconds on short OF lengths Launching level (Reflection level) : Clean the connector at the OTDR and the test cord to comply with the following levels : i) E2000 to E2000 test cord = 50 to 75 db 5.2 Presenting OTDR Test Results (Traces) OTDR-trace file name. Testing the A to B and B to A directions : The drum or cable number must form part of the file name e.g. E F1-24. (A B direction) with the OTDR connected to fibre number one and E F24-1 with the OTDR connected to fibre number 24 (B A direction). Author : BG Nel Page 9 of 10

10 5.2.2 Additional information. The following information must accompany the OTDR-trace. (a) The site or depot where the OFC drums were tested. (b) Contact details of the testing officer all OTDR-trace files and the additional information to the QAD. END OF DOCUMENT Author : BG Nel Page 10 of 10