Cabling the Switch
3-11
Figure 3-5 shows the T1 CSU/DSU LEDs. Look at the condition of the LEDs,
then examine the corresponding LED tables to better understand the indications.
Figure 3-5.
T1 CSU/DSU LEDs
Table 3-6.
T1 CSU/DSU LED Indicator
LED
Description
LED1, Yellow
Yellow alarm LED is lit when the far-end
equipment is in the red alarm condition.
LED2, Blue
Blue alarm LED is lit when receiving an
upstream failure denoted by an alarm
indication signal (AIS).
LED3, Green
Normal operation.
LED4, Red
Red alarm is lit when a loss of signal (LOS) or
out of frame (OOF) condition is detected on the
receive signal.
All LEDs off
Port disabled.
LE D 4, R ed
LED 3, G reen
LED 1, Yellow
LED 2, B lue