3 03 0 100= ×II PU IBaseEQUATION2293-ANSI V2 EN (Equation 172)where:3I0PU is the maximal zero sequence current during normal operating conditions, plus a margin of 10...20%IBase is setting of global base current all functions in the IED.10.2.3.5 Delta V and delta ISet the operation mode selector OpDVDI to Enabled if the delta function shall be inoperation.The setting of DVPU should be set high (approximately 60% of VBase) and the currentthreshold DIPU low (approximately 10% of IBase) to avoid unwanted operation due tonormal switching conditions in the network. The delta current and delta voltage functionshall always be used together with either the negative or zero sequence algorithm. IfVSetprim is the primary voltage for operation of dU/dt and ISetprim the primary currentfor operation of dI/dt, the setting of DVPU and DIPU will be given according to equation173 and equation 174.VSetprimDVPU 100VBase= ×EQUATION1765-ANSI V1 EN (Equation 173)100= ×ISetprimDIPU IBaseANSIEQUATION2385 V1 EN (Equation 174)The voltage thresholds VPPU is used to identify low voltage condition in the system. SetVPPU below the minimum operating voltage that might occur during emergencyconditions. A setting of approximately 70% of VBase is recommended.The current threshold 50P shall be set lower than the IMinOp for the distance protectionfunction. A 5...10% lower value is recommended.10.2.3.6 Dead line detectionThe condition for operation of the dead line detection is set by the parameters IDLDPU forthe current threshold and VDLDPU for the voltage threshold.Section 10 1MRK 506 334-UUS ASecondary system supervision280Application manual
