Setting of direction for offset mhoIf offset mho has been selected, one can select if the offset mho shall be Non-Directional, Forward or Reverse by setting the parameter OfffsetMhoDir.When forward or reverse operation is selected, then the operation characteristic will becut off by the directional lines used for the mho characteristic. The setting is by defaultset to Non-Directional.Setting of timers for distance protection zonesThe required time delays for different distance protection zones are independent ofeach other. Distance protection zone 1 can also have a time delay, if so required forselectivity reasons. One can set the time delays for all zones in a range of 0 to 60seconds. The tripping function of each particular zone can be inhibited by setting thecorresponding Operation parameter to OffDisable-Zone.Different time delays are possible for the phase-to-groundtLG and for the phase-to-phase tPP measuring loops in each distance protection zone separately, to furtherincrease the total flexibility of a distance protection.In the case of evolving faults or momentary current transformer saturation conditions,the pick up of the zones may get delayed. Zone timer logic improves the operating timein such conditions. The zone timer logic can be set using the parameter ZnTimerSel.The triggering signal of phase-to-ground and phase-to-phase timers can be selectedusing ZnTimerSel.3.6.4.3 Setting parametersTable 60:ZMHPDIS (21) Group settings (basic)Name Values (Range) Unit Step Default DescriptionOperation DisabledEnabled- - Enabled Operation Enable/DisableIBase 1 - 99999 A 1 3000 Base currentVBase 0.05 - 2000.00 kV 0.05 400.00 Base voltageDirMode DisabledOffsetForwardReverse- - Forward Direction modeLoadEncMode DisabledEnabled- - Disabled Load encroachment mode Off/OnReachMode OverreachUnderreach- - Overreach Reach mode Over/UnderreachOpModePG DisabledEnabled- - Enabled Operation mode Disable/Enable of Phase-Ground loopsZPG 0.005 - 3000.000 ohm/p 0.001 30.000 Positive sequence impedance setting forPhase-Ground loopTable continues on next page1MRK504116-UUS C Section 3IED application281Application manual
