Siemens SCALANCE X320-3LD FE Operating Instructions Manual page 213

Media module Fiber-optic cable
type
MM992-2LD 9/125 µm
single mode fiber
MM992-2LH 9/125 µm
single mode fiber
MM992-2LH+ 9/125 µm
single mode fiber
MM992-2ELH 9/125 µm
single mode fiber
Copper / fiber-optic cables
Table 8- 131 Permitted cable lengths (copper cable/fiber-optic cable) for the SFP media module
Media module
MM992-2SFP
You will find further information in the compact operating instructions "Transceiver SFP/SFP+".
*)
Attenuators
Transceivers of the types LH, LH+, ELH and ELH200 are designed for long distances and
therefore send more power than they can receive.
If you establish a connection between such transceivers with a short cable length, use
attenuators. Attenuators increase the attenuation and therefore protect the receiving diode.
Select the attenuation so that the transmit power (transmitter output) behind the attenuator is
lower than the maximum received power (input power):
Transmitter output max. [dBm] - attenuator [dB] < input power max. [dBm]
Recommendation for the attenuation of the attenuator on a connection with the same
transceivers:
Transceiver type
LH
LH+
ELH, ELH200
If you have established a connection on a pluggable transceiver with a short cable length, it
is possible that the transmitter will be turned off. In this case, pull the transceiver and plug it
in again.
SCALANCE X-300
Operating Instructions, 05/2016, A5E01113043-20
Max. permitted
cable length
10 km
40 km
70 km
120 km
Max. permitted cable length
Depending on the SFP transceiver used.
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8.9 MM900 technical specifications
Attenuation
≤0.5 dB/km at 1310 nm; maximum insertion loss 0.5 dB; 6 dB
max. permitted FO cable attenuation at 3 dB link power mar-
gin
≤0.4 dB/km at 1550 nm; maximum insertion loss 0.5 dB;
18 dB max. permitted FO cable attenuation at 2 dB link pow-
er margin, minimum cable attenuation 3 dB
≤0.28 dB/km at 1550 nm; maximum insertion loss 0.5 dB;
21 dB max. permitted FO cable attenuation at 2 dB link pow-
er margin, minimum cable attenuation 8 dB
≤0.225 dB/km at 1550 nm; maximum insertion loss 0.5 dB;
27 dB max. permitted FO cable attenuation at 2 dB link pow-
er margin, minimum cable attenuation 8 dB
Attenuator
6 dB ... 12 dB
12 dB ... 20 dB
16 dB ... 24 dB
Technical specifications
213