Hubbel RFL PLC Hybrid Pro, Руководство пользователя

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RF-MCHYBRIDPRO-01
Hubbell Power Systems, Inc. – RFL™ Products
June 2019 12 973.334.3100
3.4 Two Transmitters, Two Receivers (FSK and On-Off/DCB)
TX1
TX2/RX2
(2W)
BAL
SK
RX1
to/from Line Tuner
Figure 5 – Two Transmitters, Two Receivers (FSK and On-Off/DCB)
The application in
F
IGURE
5 is like F
IGURE
3 – one balanced hybrid, one skewed hybrid, and two
individual relaying channels. The main difference here is that TX2/RX2 is a 2-wire DCB channel (the
transmit and receive are directly tied together) so there is only one coax connection to/from the unit.
In
these cases, the DCB channel TX/RX signals are treated as a transmitter. Like a transmitter, they are
connected to the input of a balanced hybrid.
3.5 Two Transmitters, Two Receivers, Phase-to-Phase Coupled
(low-loss method)
TX1
TX2
BAL
SK
RX1
RX2
SPL
to/from Line Tuner A
to/from Line Tuner B
Figure 6 – Two Transmitters, Two Receivers, Phase-to-Phase Coupled (low-loss method)
F
IGURE
6 shows two transmitters and two receivers in a phase-to-phase coupling application. Here,
once the signals have been combined onto a single coax connection (same as the circuit in F
IGURE
3 ),
the signals are “split”. Then, two coax cables are run from the splitter out to the switchyard, adding
redundancy and dependability. There are variations of the connection scheme – some line tuners can be
equipped with a splitter circuit – but the scheme depicted in
F
IGURE
6 will provide the best reliability
for this phase-to-phase application. This is because there will be two coax cables going out to the tuner,
and ideally these will be run in separate cable trays.