ABB REB670 Series - Page 430

OptoPower has two settings: LowPower and HighPower .
Short-range LDCM: Use LowPower for fibres 0 – 1 km and HighPower for fibers greater than 1
km.
Medium-range LDCM: Typical distance 80 km for both LowPower and HighPower .
Long-range LDCM: Typical distance 120 km for both LowPower and HighPower .
An optical budget calculation should be made for the actual case. For medium range LDCM and
long range LDCM the recommendation is to use the
LowPower setting to minimize the power
consumption and keep the heat dissipation at minimum.
The
HighPower setting adds 3 dBm extra optical power and can be used to increase the
margin at distances close to maximum.
Table 57: Optical budgets with C37.94 protocol
Type of LDCM Short range (SR) Short range (SR) Medium range (MR) Long range (LR)
Type of fibre Multi-mode fiber
glass 50/125 μm
Multi-mode fiber
glass 62.5/125 μm
Single-mode fiber
glass 9/125 μm
Single-mode fiber
glass 9/125 μm
Modem type 1MRK0002122-AB 1MRK0002122-AB 1MRK002311-AA 1MRK002311-BA
Contact type ST ST FC/PC FC/PC
Minimum output
power
1)
–21 dBm –13.7 dBm –3.2 dBm –1.3 dBm
Minimum receiver
sensitivity
–32.5 dBm –32.5 dBm –30 dBm –30 dBm
Optical link
budget
2)
11.5 dB 18.8 dB 26.8 dB 28.7 dB
1) Minimum output power is measured with 1 m of the selected fiber and the high power mode.
2) The optical budget includes a satisfactory margin for aging in transmitter and receiver during 20–30 years.
Table 58: Example of input data for calculating the optical budget (maximum distance)
Type of LDCM Short range (SR) Short range (SR) Medium range (MR) Long range (LR)
Type of fibre Multi-mode fiber
glass 50/125 μm
Multi-mode fiber
glass 62.5/125 μm
Single-mode fiber
glass 9/125 μm
Single-mode fiber
glass 9/125 μm
Modem type 1MRK0002122-AB 1MRK0002122-AB 1MRK002311-AA 1MRK002311-BA
Typical attenuation
in fibre-optic
cables
3 dB/km 3 dB/km 0.32 dB/km 0.21 dB/km
Attenuation/
Contact
1.5 dB/ST 1.5 dB/ST 0.3 dB/FC/PC 0.3 dB/FC/PC
Factory splice
attenuation
0.5 dB/splice
0.3 splices/km
0.5 dB/splice
0.1 splices/km
0.08 dB/splice
0.1 splices/km
0.08 dB/splice
0.1 splices/km
Repair splices 0.25 dB/splice
0.1 splices/km
0.25 dB/splice
0.1 splices/km
0.1 dB/splice
0.05 splices/km
0.1 dB/splice
0.05 splices/km
Fiber margin for
aging
0.1 dB/km 0.1 dB/km 0.01 dB/km 0.01 dB/km
Section 18 1MRK 505 370-UEN D
Remote communication
424 Busbar protection REB670
Application manual