Nortel SONET AccessNode Manual page 38

2-20 DS3 tests, STS-1 tests, and optical in-bay tests
Procedure 2-3 (continued)
Testing optical protection switching
Step
AccessNode Vol 3B 323-3001-221 Issue 2.0
Action
CAUTION
Risk of damage to the optical receiver
For the NT7E02 OC-12 long-reach (LR) interface circuit
pack, received optical power must not exceed the following
safe level: −6.0 dBm. Refer to Site Installation Planning and
Engineering , 323-3001-200 in the Engineering,
Configuration, and Ordering Guide , Volume 1.
There are no damage levels for NT7E01 IR and LR,
NT7E02 IR, and NT7E05 IR and LR optical interfaces.
CAUTION
Risk of attenuator damage
If the attenuation does not change after 1 full turn of the
adjustment screw, stop turning in that direction. Instead,
turn the screw in the opposite direction to restore the circuit
pack to within the operating range.
CAUTION
Risk of receiver damage
Received optical power must not exceed − 9.0 dBm and
− 6.0 dBm for the long-reach (LR) OC-3 and OC-12 optical
interface circuit packs respectively. Received optical power
must not exceed − 6.0 dBm and − 2.0 dBm for the
intermediate-reach (IR) OC-3 and OC-12 optical interface
circuit packs respectively.
Refer to Site Installation Planning and Engineering ,
323-3001-200 in the Engineering, Configuration, and
Ordering Guide , Volume 1.
If the optical loop is very short, insert attenuation between
the OC-3/OC-12 transmitter and receiver, to limit the
received optical power to a safe level (for example,
− 15 dBm).
There are no damage levels for NT7E01 IR and LR, NT7E02
IR and NT7E05 IR, and LR optical interfaces.
—continued—