GE B90 Instruction Manual page 300

PRODUCT SETUP
The LEDs can be customized to illuminate when a selected FlexLogic operand is in the logic 1 state. The trip and alarm
LEDs can also be customized in a similar manner. To ensure correct functionality of all LEDs, an LED test feature is also
provided.
5.3.11.3 LED test
SETTINGS  PRODUCT SETUP  USER-PROGRAMMABLE LEDS  LED TEST
 LED TEST

When enabled, the LED test can be initiated from any digital input or user-programmable condition, such as a user-
programmable pushbutton. The control operand is configured under the
LEDs, including the LEDs of the optional user-programmable pushbuttons.
For the enhanced and standard front panels, the test consists of the following 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 as
long as the control input is on, up to a maximum of one minute. After one minute, the test ends.
2. All the LEDs are turned off, and then one LED at a time turns on for one second, then back off. The test routine starts at
the top left panel, moving from the top to bottom of each LED column. This test checks for hardware failures that lead
to 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 one second, then back on. The test routine starts at the top
left panel moving from top to bottom of each column of the LEDs. This test checks for hardware failures that lead to
more than one LED being turned off from a single logic point. This stage can be interrupted at any time.
5
For the graphical front panel, the test consists of the following stages:
1. All 22 LEDs on the relay are illuminated. This is a quick test to verify if any of the LEDs is "burned." This stage lasts as
long as the control input is on, up to a maximum of one minute. After one minute, the test ends.
2. All the LEDs are turned off, and then one LED at a time turns on with the orange color for one second, then back off.
The test routine starts at the top left panel, moving from the top to bottom for all 14 LEDs. Then the eight pushbutton
LEDs are tested in the same manner. This test checks for hardware failures that lead to 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 with the orange color. One LED at a time turns off for one second, then back on. The test
routine starts at the top left panel moving from top to bottom for all 14 LEDs. Then the eight pushbutton LEDs are
tested in the same manner. This test checks for hardware failures that lead to more than one LED being turned off
from a single logic point. This stage can be interrupted at any time.
4. Additionally, stages 2 and 3 are repeated twice for the five device status LEDs and nine event cause LEDs, one time
with green color on and the other with red color on.
When testing is in progress, the LEDs are controlled by the test sequence, rather than the protection, control, and
monitoring features. However, the LED control mechanism accepts all the changes to LED states generated by the relay
and stores the actual LED states (on or off) in memory. When the test completes, the LEDs reflect the actual state resulting
from relay response during testing. The reset pushbutton does not clear any targets when the LED Test is in progress.
A dedicated FlexLogic operand,
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 be
interrupted. The test responds to the position and rising edges of the control input defined by the
setting. The control pulses must last at least 250 ms to take effect. The following diagram explains how the test is
executed.
5-108
LED TEST FUNCTION:

Disabled
LED TEST CONTROL:

Off
PROGRESS, is set for the duration of the test. When the test sequence is initiated,
LED TEST IN
B90 LOW IMPEDANCE BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
Range: Disabled, Enabled
Range: FlexLogic operand
setting. The test covers all
LED TEST CONTROL
LED TEST CONTROL