ABB RET670 - Optical Budget Calculation for Serial Communication with SPA;IEC

9.4 Optical budget calculation for serial communication
with SPA/IEC
Table 12: Example
Distance 1 km
Glass
Distance 25 m
Plastic
Maximum attenuation - 11 dB - 7 dB
4 dB/km multi mode: 820 nm - 62.5/125 um 4 dB -
0.16 dB/m plastic: 620 nm - 1mm - 4 dB
Margins for installation, aging, and so on 5 dB 1 dB
Losses in connection box, two contacts (0.5 dB/contact) 1 dB -
Losses in connection box, two contacts (1 dB/contact) - 2 dB
Margin for 2 repair splices (0.5 dB/splice) 1 dB -
Maximum total attenuation 11 dB 7 dB
Section 9 1MRK 504 088-UEN C
Establishing connection and verifying the SPA/IEC- communication
92
Installation and commissioning manual