Sea Technology

FEB 2018

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

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20 ST | February 2018 at each calibration interval to protect the unit from going out of specification and to avoid expensive repair costs. Industry Calibration Service Levels Level one service is a self-check and sample point evaluation and calibration, which is suitable for yes/no checks. However, level one is not recommended for quantitative measurements. Level two service is Tra-Cal Lab's standard-level calibration for measurement instru- ments. This includes a full evaluation and American Na- tional Standards Institute (ANSI) Z540 standard, without data calibration, to 100 percent OEM specifications, comprehensive instrument inspection and 100 percent parametric evaluation and calibration on all inputs and outputs (I/O) and all options, across all OEM specifica- tions. An auditable hierarchy of procedures, with OEMs as first authority, is used. In addition, preventive mainte- nance is performed, including standard fuses and most batteries. Level three service adds ANSI-Z540 "as found" and "as adjusted" data for each parameter to the level two service described above. Level four service adds uncertainty computations and audited International Organization for Standardization (ISO) third-party over- sight to the level three service. Level five service adds guardbanding to the level four service. Guardbanding is the requirement for verification and documentation that quantities are within specified tolerances. The probabili- ty that incorrect acceptance decisions (false accepts) will result from calibration tests must not exceed 2 percent. Test Methodology Tra-Cal Lab calibrated the Navy's Keysight N9030A PXA Signal Analyzer in January 2017 to meet the full manufacturer's standard level without customer data. This involved a series of tests to ensure the accuracy and integrity of the analyzer. For proper calibration, the sig- nal analyzer was evaluated by following these steps: 1) instrument preparation; 2) self-test; 3) test setup range from 1 to n (comprehensive evaluation, calibration, ad- justment and/or realignment to full OEM specifications with 100 percent capture of "as found" and "as adjust- ed" data, uncertainty computation, per measurement parameter against National Institute of Technology's traceable reference standards); 4) adjustments and retest, if required; 5) repair or alignment if adjustment/function failure; and 6) preventive maintenance. The PXA is ideally suited for high-performance re- search and development (R&D) applications in aero- space, defense and commercial wireless communica- tions. The PXA analyzes signals over wider bandwidths, reduces measurement uncertainty and reveals previous- ly hidden signals with noise floor extension. By using a combination of standards traceable to the National Institute of Technology and vector signal analysis (VSA) software, software for demodulation and vector signal analysis, Tra-Cal Lab can verify that the unit meets manu- facturers' specifications. The complete verification of this unit consists of approximately 535 data points depend- ing on the options installed. Due to the complex nature Save time and money locating subsea cables - Locates and tracks cables - Finds faults and breaks - Use on land & underwater - Audio and Visual output - Commercial construction - Calculate burial depth with a JW Fishers CT-1 Cable Tracker. JW Fishers Mfg., Inc. 1953 County Street East Taunton MA 02718 USA (800)822-4744 or (508)822-7330 Email:

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