CHAPTER 5: SETTINGS TESTINGL90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL 5-4295The Forcible mode is intended for testing involving forcing relay operation by test signal injection and verifying correctrelay output. This mode is also for tests to verify the relay outputs (both contact and communications) have the intendedimpact on specific power system devices or on specific other substation automation devices. Contact outputs can beselectively enabled or forced as described in the following two sections. Shared outputs to bricks have their test mode flagraised, which results in their value only being accepted by relays also in forcible mode. GOOSE transmissions have the"simulation" flag set, which results in these only being accepted by other devices that have their "Sim" data attribute set.The "Sim" data attribute in the relay is set, so that if GOOSE messages are received with the "simulation" flag set, these areused in place of the normal messages. The quality attribute of values that are output via 61850 MMS services are set to"valid" + "test," which signals that the values should not be used for operational purposes.Otherwise, the UR remains fully operational while in the Forcible test mode, allowing for various testing procedures. Inparticular, the protection and control elements, and FlexLogic function normally. Other than the IEC 61850 protocol,communications based inputs and outputs remain fully operational. The test procedure must take this into account. DirectI/O channel tests and PMU tests are usable on applicable models.The test mode can be selected either through the front panel, through EnerVista UR Setup, or through IEC 61850 control toLLN0.Mod. LLN0.Mod.ctlVal "on" selects Disabled, "test/blocked" selects Isolated, and "test" selects Forcible. The TEST MODEFUNCTION setting can only be changed by a direct user command. Following a restart, power up, settings upload, orfirmware upgrade, the test mode remains at the last programmed value. This allows a UR that has been placed in isolatedmode to remain isolated during testing and maintenance activities.5.11.2 Test mode forcingSETTINGS TESTING TEST MODE FORCINGWhen in Forcible mode, the operand selected by the TEST MODE FORCING setting dictates further response of the L90 totesting conditions, as described in the following two sections.The test mode state is indicated on the relay front panel by a combination of the Test Mode LED indicator, the In-ServiceLED indicator, and by the critical fail relay, as shown in the following table.Table 5-45: Test mode operation5.11.3 Phasor Measurement Unit test valuesSETTINGS TESTING PMU TEST VALUES PMU 1 TEST VALUES TESTING TEST MODE FORCING:OnRange: FlexLogic operandTEST MODEFUNCTIONIn-serviceLEDTest modeLEDCritical failrelayTEST MODEFORCINGContact input and output behaviorDisabled Unaffected Off Normal No effect NormalIsolated Off On De-energized No effect Contact outputs disabledForcible Off Flashing De-energized Off NormalOn Controlled by forcing featuresOn restart, the TEST MODE FORCING setting and the force contact input and force contact output settings revert totheir default states. PMU 1 TEST VALUES PMU 1 TESTFUNCTION: DisabledRange: Enabled, Disabled PMU 1 VA TESTMAGNITUDE: 500.00 kVRange: 0.00 to 700.00 kV in steps of 0.01 PMU 1 VA TESTANGLE: 0.00°Range: –180.00 to 180.00° in steps of 0.05
