Nortel SONET AccessNode Manual page 30

2-12 DS3 tests, STS-1 tests, and optical in-bay tests
Procedure 2-2 (continued)
Measuring optical receiver performance
Step
5
AccessNode Vol 3B 323-3001-221 Issue 2.0
Action
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.
Adjust the VOA to obtain the specified minimum reading of received optical
power, as listed below for your optical interface circuit pack:
PEC
NT7E01CA/CB/CC/CD
NT7E01DA/DB/DC/DD
NT7E02KA/KB/KC/KD
NT7E02LA/LB/LC/LD
NT7E05AB/AC/AD
NT7E05BB/BC/BD
Note : The above values apply to Nortel-to-Nortel proprietary links. They
also apply to Bellcore TR-NWT-000253 Midspan-meet links, with the
following exceptions:
NT7E05AB/AC/AD
NT7E05BB/BC/BD
—continued—
Module Minimum receiver
power (P
− 34.0 dBm
OC-3 LR
− 28.0 dBm
OC-3 IR
− 32.0 dBm
OC-12 LR
− 24.5 dBm
OC-12 IR
OC-12 VTBM LR –29.5 dBm
OC-12 VTBM IR –28.0 dBm
OC-12 VTBM LR –28.0 dBm
OC-12 VTBM IR –28.0 dBm
)
R min