Eaton COOPER POWER Series Installation, Operation, And Maintenance Instructions And Parts Replacement Information
Also see for COOPER POWER SERIES: Installation and operation instructionsInstallation instructionsInstallation instructionsInstallation and operation instructionsOperation instructions
                        | |
Contents
| 
Insulating liquid maintenanceSampling insulating liquidotee:N A sample of the liquid should be taken when the unitis warmer than the surrounding air to avoid conden-sation of moisture on the liquid. Liquid samples mustbe drawn from the sampling valve located at thebottom of the transformer tank.Containers used for sampling liquid should be clean and drylarge mouth glass bottles.Do not permit the fluid to splash into the receivingcontainer. Splashing can introduce air and moisture intothe fluid. Rinse the bottle three times with the liquid beingsampled. Make sure the liquid being sampled is representa-tive of the liquid in the unit.Test samples should be taken only after the liquid hassettled for some time – eight hours for a barrel, up toseveral days for a large transformer. Cold insulating liquidis much slower in settling. Liquid samples from the trans-former should be taken from the sampling valve at thebottom of the tank.WARNINGDo not lower fluid in tank to a level below the topof the core clamp Insufficient fluid risks unit failure,which could result in severe personal injury or death toexposed personnelWhen sampling, a metal or non rubber hose must be usedbecause oil leaches the sulfur found in rubber. The presenceof sulfur can prove harmful to transformer components.When drawing samples from the bottom of the transformeror large tank, sufficient liquid must first be drawn off toensure that the sample will be from the bottom of the tank,and not the liquid stored in the sampling pipe.Testing insulating liquidFor testing the dielectric strength of insulating liquids,follow the procedure specified by the American Societyfor Testing Materials in ASTM D-877, "Standard Method forTesting Electrical Insulating Oils."If, at any time, the dielectric strength of the liquid dropsbelow 26 kV, it should be filtered until it tests at 26 kV orbetter.Filtering insulating liquidTransformer oil, R-Temp fluid or Envirotemp™ FR3™ fluidcan be filtered by means of a filter press. The filter press iseffective for removing all types of foreign matter, includingfinely divided carbon and small amounts of moisture. Thepurifier equipment consists of a specifically proportionedfilter press, a positive volume gear pump, driving motor,combined drip pan and mixing tank, necessary piping,valves, strainer, gauges and a drying oven.Filtration should be continued until the dielectric test of theinsulating liquid is 26 kV or better.CAuTIONWhen filtering any insulating fluid, the filteringequipment must be free of contaminants and otherliquids The presence of other liquids may alter thephysical and electrical characteristics of the fluidApplicable standards1. IEEE Std C57.91™-2011 standard, "Guide for LoadingMineral Oil Immersed Transformers."2. IEEE Std C57.93™-2007 standard "Guide for Installationand Maintenance of Liquid Immersed PowerTransformers."3. IEEE Std C57.106™-2006 standard, "Guide forAcceptance and Maintenance of Insulating Oil inEquipment."4. ASTM Specification #D 877, "The Standard Method ofTesting Electrical Insulating Oils."5. IEEE Std C57.121™-1998 standard, “Guide forAcceptance and Maintenance of Less FlammableHydrocarbon Fluid in Transformers.”R-Temp fluid-filled transformersPeriodic maintenance tests for R-Temp fluid-filledtransformers should be performed on essentially the sameschedule as would be used for conventional mineral oil-filledtransformers of similar application. The same type ofsampling techniques should be used. Basic recommendedtests for R-Temp fluid-filled transformers are dielectricstrength, moisture content, and flash and fire point.Dielectric strengthAlthough the transformer should operate satisfactorilywith a fluid dielectric strength of 22 kV, an R-Temp fluiddielectric strength below 25 kV is an indication of excessivecontamination. In this case, the R-Temp fluid should bereplaced or filtered to remove the moisture or particulatecontamination.The dielectric strength of R-Temp fluid should be tested inaccordance with ASTM D 877.14SubStation tranSformer inStallation and partS replacement information MN202002EN JUNE 2016 |
Related manuals for Eaton COOPER POWER SERIES
This manual is suitable for:
manualsdatabase
Your AI-powered manual search engine