GE D90 Plus Instruction Manual page 72

ELECTRICAL INSTALLATION
62
Figure 31: Link LEDs for fiber, RS422, and G.703 modules
The following table describes the operation of the link LEDs.
Table 4: Link LED operation
Protocol LED indications
Red, solid Green, solid
IEEE Loss of Signal detected,
C37.94 signal but not receiving
valid data
Direct Loss of Signal detected,
fiber signal but not receiving
valid data
G.703 Loss of Signal detected,
signal but not receiving
valid data
RS422 Loss of Clock detected,
clock but not receiving
valid data
Green, blinking
Signal detected
and receiving valid
data; yellow bit
alarm not set
Signal detected
and receiving valid
data
Signal detected
and receiving valid
data
Clock detected
and receiving valid
data
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 3: INSTALLATION
Yellow, blinking
Signal detected, receiving valid
data and the received yellow bit
alarm is set; the yellow bit indicates
that remote unit is not receiving
valid data
Not used
Not used
Not used