Hubbel RFL PLC Hybrid Pro, Руководство пользователя

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RF-MCHYBRIDPRO-01
Hubbell Power Systems, Inc. – RFL™ Products
June 2019 23 973.334.3100
4.5 Splitter/Combiner
F1 0°
F2 180°
IN 1
F1 0°
SPL/COM
IN 2
F2 0°
LINE 1
LINE 2
F1 180°
F2 0°
Figure 22 – Splitter/Combiner, Functional Diagram
The splitter/combiner is used to “split” and “combine” signals for phase-to-phase coupling applications
(center-phase-to-outer-phase). It is typically installed between two skewed hybrids and the line tuners –
one-line tuner for each phase of the “phase-to-phase” coupling scheme (see
F
IGURE
7 in Section 3 ).
The 180-degree phase relationship between the outputs LINE 1 and LINE 2 is required for maximum
propagation down the transmission line in center-phase-to-outer-phase coupling schemes.
The advantage of using this device over the splitter is that there is no single coax cable on which all the
signals travel. Typically, IN1 is fed by a skewed hybrid which carries signals for one relaying system,
and IN2 is fed by another skewed hybrid which carries signals for a redundant or backup relaying
system. In this way, there is no common coaxial connection of the independent relaying systems.
Compare
F
IGURE
6 and F
IGURE
7 in Section 3 for reference.
The disadvantage of using this device over the splitter is that the splitter/combiner adds about 9 to 10
dB of loss to the channel (this figure includes losses through devices at both ends of the channel). In
contrast, the splitter adds no loss. These factors must be considered when choosing the appropriate
devices for different power line carrier applications.
IN 1
IN 2
SPL
SPL
BAL
BAL
LINE 1
LINE 2
Figure 23 – Splitter/Combiner, Equivalent Circuit