ABB RET670 Commissioning Manual page 93

1MRK 504 165-UUS -
Establishing connection and verifying the IEEE C37.118/1344 communication
Transformer protection RET670 2.2 ANSI
Commissioning manual
14
12
62.5/125 µm
10
8
6
50/125 µm
4
2
0
0 0.5 1.0 1.5
FIBER OPTIC CABLE LENGTH - km
IEC11000409 V1 EN
Figure 18: Optical power budget for fiber optic cable lengths
As shown in the graph, if one uses a 62.5/125 µm fiber, the value under the 62.5/125 µm
curve represents the remaining optical budget at any link length, which is available for
overcoming non-fiber cable related losses.
Losses in the connectors and splices are typically 0.3dB/connection. The user must
reserve 3dB spare for the uncertainty of the measurements.
2.0 2.5 3.0 3.5 4.0
IEC11000409_1_en.vsd
Section 9
87