5-58 L90 Line Current Differential System GE Multilin5.2 PRODUCT SETUP 5 SETTINGS5The 48 amber LEDs on relay panels 2 and 3 can be customized to illuminate when a selected FlexLogic operand is in thelogic 1 state. The trip and alarm LEDs on panel 1 can also be customized in a similar manner. To ensure correct functional-ity of all LEDs, an LED test feature is also provided.b) LED TESTPATH: SETTINGS PRODUCT SETUP USER-PROGRAMMABLE LEDS LED TESTWhen enabled, the LED test can be initiated from any digital input or user-programmable condition such as user-program-mable pushbutton. The control operand is configured under the LED TEST CONTROL setting. The test covers all LEDs,including the LEDs of the optional user-programmable pushbuttons.The test consists of three stages.1. All 62 LEDs on the relay are illuminated. This is a quick test to verify if any of the LEDs is “burned”. This stage lasts aslong as the control input is on, up to a maximum of 1 minute. After 1 minute, the test will end.2. All the LEDs are turned off, and then one LED at a time turns on for 1 second, then back off. The test routine starts atthe top left panel, moving from the top to bottom of each LED column. This test checks for hardware failures that leadto more than one LED being turned on from a single logic point. This stage can be interrupted at any time.3. All the LEDs are turned on. One LED at a time turns off for 1 second, then back on. The test routine starts at the top leftpanel moving from top to bottom of each column of the LEDs. This test checks for hardware failures that lead to morethan one LED being turned off from a single logic point. This stage can be interrupted at any time.When testing is in progress, the LEDs are controlled by the test sequence, rather than the protection, control, and monitor-ing features. However, the LED control mechanism accepts all the changes to LED states generated by the relay andstores the actual LED states (on or off) in memory. When the test completes, the LEDs reflect the actual state resulting fromrelay response during testing. The reset pushbutton will not clear any targets when the LED Test is in progress.A dedicated FlexLogic operand, LED TEST IN PROGRESS , is set for the duration of the test. When the test sequence is initi-ated, the LED TEST INITIATED event is stored in the event recorder.The entire test procedure is user-controlled. In particular, stage 1 can last as long as necessary, and stages 2 and 3 can beinterrupted. The test responds to the position and rising edges of the control input defined by the LED TEST CONTROL set-ting. The control pulses must last at least 250 ms to take effect. The following diagram explains how the test is executed. LED TESTLED TEST FUNCTION:DisabledRange: Disabled, Enabled.MESSAGE LED TEST CONTROL:OffRange: FlexLogic operand
