CHAPTER 5: SETTINGS SYSTEM SETUPL30 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL 5-1475These settings ensure that the 87L element correctly applies magnitude and phase compensation for the in-zonetransformer. To accommodate for the difference in CT ratios at line terminals, use the SETTINGS GROUPED ELEMENTS SETTING GROUP 1(6) LINE DIFFERENTIAL ELEMENTS CURRENT DIFFERENTIAL CURRENT DIFF CT TAP setting. It is importantto properly program the in-zone transformer setting for all terminals to ensure correct 87L performance.IN-ZONE TRANSFORMER CONNECTION — This setting indicates the presence and group connection of the in-zonetransformer. The winding angle selection specifies the phase shift of the remote terminal side winding with respect to thelocal terminal side winding. For example, for the Dy1 group where the delta winding is connected to the local terminal side,and wye winding is connected to the remote terminal side, you select “30° lag” for the local terminal side. (At the remoteterminal relay, select “330° lag” for this transformer group connection.) If there is no in-zone transformer connected, thenprogram this setting as “None” (note that the “0° lag” value does not correspond to “None”). Only one in-zone transformeris allowed for both two-terminal and three-terminal applications. Enabling in-zone transformer functionality forces the L30to automatically remove the zero-sequence component from all terminals currents. It also disables ground differential87LG functionality and zero-sequence current removal functionality defined by the ZERO SEQ CURRENT REMOVAL setting.Do not set the IN-ZONE TRANSFORMER CONNECTION setting to "None" at one terminal and set other terminals to a valueother than "None." 87L is blocked under these circumstances.TRANSFORMER LOCATION — This setting selects the transformer location and applies only when the IN-ZONE TRANSFORMERCONNECTION setting is other than “None.”Select the “LOCAL-TAP” value if the transformer is present between the local terminal and the tap point or for two-terminalapplications.Select “REM1-TAP” if the transformer is present between remote terminal 1 and the tap point.Select “REM2-TAP” if the transformer is present between remote terminal 2 and the tap point.Figure 5-64: Illustration of in-zone transformer for two-terminal and three-terminal lines5.5.5 BreakersSETTINGS SYSTEM SETUP BREAKERS BREAKER 1(2) TRANSFORMER LOCATION:LOCAL-TAPRange: LOCAL-TAP, REM1-TAP, REM2-TAPThe L30 is provided with this optional feature, specified as an option at the time of ordering. Using the ordercode for your device, see the order codes in chapter 2 for details. BREAKER 1 BREAKER 1FUNCTION: DisabledRange: Disabled, Enabled BREAKER1 PUSH BUTTONCONTROL: DisabledRange: Disabled, Enabled
