Stage 1- On line tests & Operational, design & historic information
This would be a review of all engineering design and operational documents, Past test data including regular scans with on-line test methods. New oil tests would be undertaken. This should identify the common problems and prioritize which offline test is more important in second phase for detail review Activities: External inspection, IR/UHF surveys, and oil tests for main tank and LTC including DGA and FURAN, Checking of pump operation and fans.
Stage 2 – Off-line test on all units
Focus on those that indicate risk from Sage-1.Undertake a range of outage tests to investigate issues, and correlate with assessment from stage-1. Activities: Off line tests- PF/Cap, Winding and insulation resistance, SFRA, Turns Ratio, Leakage Reactance, Bushing, Surge arrester testing, OLTC operation and dynamic contact resistance measurement, Moisture analysis of paper insulation by dielectric method (PDC FDS)
Stage 3 – Classification of Transformer and recommendation for future test:
All units will be assessed in terms of design groups with problems, overall condition, and thermal mechanical and dielectric condition. Assessment will be based on
Operational problems and design group historyOil condition of main tank & selectorsThermal ageing and hot spots in winding and connectionDielectric conditionMechanical condition
The test frequency and recommended test will be modified after each cycle of measurement depending upon the condition of Transformer.
Owing to our enriched industrial experience, we are devoted towards offering a premium gradetesting service of Current Transformers. Our special team of adept professionals uses their vast knowledge and expertise to carry out this service within the scheduled time-frame. Our highly experienced professionals precisely check all the parameters associated to this service and perform it in the best possible manner. Further, the offered service is rendered as per the clients’ specific needs with respect to their budgetary constraints.
CT winding resistance measurement
CT excitation characteristic according to IEC 60044-1 and IEEE C57.13. for knee-point voltages.CT ratio measurement, phase and polarity measurementDetermination of accuracy limiting factor, instrument security factor, Test of CTs for knee-point voltages.Capacitance and dissipation factor measurement of the main insulation and bushingsPartial discharge measurements of CTs.Moisture analysis of paper insulation by dielectric method.Power Cable