11.Application应用TheURF25/10monitoringrelayisanalarmdeviceforoil-insulatedhigh-dutytappingswitchesoftransformerfromdamageasmightbecausedbyfailureofthetappingswitchsystemortheapplicationofexcessivecurrents(strongarc)duetoatransformerdefect.URF25/10油流继电器是有载调压分接开关的一个报警装置。当分接开关内部出现故障或由于变压器本体故障引发短路电流（大电弧）时，可起到保护分接开关的作用。Onresponsethemonitoringrelaywillgenerateacontinuouspulseoperatingthecircuitbreakerofthetransformertobeprotectedanddisconnectingthelatterfromthesourceofsupply.Observingtheinstructionsoftheplantoperator,thetransformercanberestartedonlyafteroperationofthetestandresetbutton.当故障时，油流继电器持续发出信号以断开变压器的主断路器，这样可以保护后级电气装置不受损坏。按照生产商操作手册的说明，仅当操作油流继电器上的试验和复位按钮后，变压器才能合闸继续运行。Themonitoringrelayisavailablewithsingleanddouble-contactcircuitsystem.Onresponseofthebaffleplateduetoanincreasedoilflow,thedouble-contactcircuitprovidestwosignals,henceimprovingoperationalsafetyoftheequipment.油流继电器可以提供单触点和双触点两种形式。当油流继电器内动作挡板由于油流作用动作时，双触点电路可提供两组独立的信号，这样可以进一步提高设备的安全性。2.Construction结构Themonitoringrelayconsistsofthefollowingsub-assemblies:油流继电器由以下部件组成：1)Casingassembly机壳2)Coverassembly机盖3)Switchmechanism信号机构2.1Casingassembly机壳Thecasingconsistsofweatherprooflightmetalcasting.Tochecktheswitchsystemforproperfunction,thecasingisprovidedwithinspectionglassesarrangedoppositeeachother.Onrequest,theinspectionglassescanbeprovidedwithhingedlids.机壳由防风雨的轻金属材料制成。机壳前后各自安装了一个观察窗，以便于检查内部信号机构的工作情况。如需要的话，观察窗处可另加可旋转的保护盖。2.2Coverassembly机盖Thecoverconsistsofaweatherprooflightmetalcasting.Theconnectionbox,thetestandresetbuttonandatechnologicalbleederscrewarearrangedabovethecover.机盖由防风雨的轻金属材料制成。上面安装有接线盒，试验和复位按钮和放油用的螺栓。Inadditiontotheearthconnection,theconnectionboxaccommodatestheelectricbushingsinthefloor.Theconnectionboxisclosedbyahingedcapsothatitisaccidental-shocksafeandnodirtgetinsidethebox.除有接地点外，接线盒内还提供了信号引出的接线柱。接线盒上有一个盖子可以防止意外撞击和灰尘进入内部。TheconnectingcablecanbeinsertedoptionallythrougheitherPG16screwedconduit.The2testandresetbuttoniscoveredbyacapnut.信号连接电缆可以从任一个PG16螺纹管内接入。试验和复位按钮上有一个螺帽保护。2.3Switchmechanism信号机构Theswitchmechanismconsistsofthefollowingmajorcomponents:信号机构由以下部件构成：-Frameassupportelement支撑框架-Functionalelement,switchsystem动作单元，开关系统-Mechanicaltestingequipmentforfunctionaltesting测试动作情况的机械试验装置Theswitchingsystemconsistsofthefollowingcomponents:开关系统由以下部件构成：-Baffleplate挡板-Switchingmagnet动作磁铁-Magneticswitch磁性开关Thebaffleplateisretainedinitsnormalandresponsepositionsbypermanentmagnets.Viaalinktheswitchingmagnetisfirmlyconnectedwiththebaffleplateandinitiatesthecontact-makingprocessofthemagneticswitchatacertainoilflow.挡板由永久磁铁控制在正常工作位置或是在动作位置。通过一个干簧管，动作磁铁被紧密连接在挡板上。当油流速度超过整定值后，动作磁铁就会带动磁性开关的触点吸合。3.Modeofoperation操作方式Iftheoilflowfromthetappingswitchtotheexpansiontankisexcessiveorinadmissible,themonitoringrelaywillbetripped.Theoilflo...
