OPU-1
UNIVERSAL POWER-LINE CARRIER SYSTEM TYPE OPU-1
GENERAL DESCRIPTION - Rev 7 (May 2019)
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With a QAM digital channel, transmission at 40.5 kbit/s in an 8 kHz bandwidth and at
20.25 kbit/s over a 4 kHz bandwidth is also possible, over a single frequency slot in
superimposed bands or two slots in non-adjacent bands in both cases.
At 40.5 kbit/s, the transmission and reception channels, each of 8 kHz, can be adjacent,
resulting in a total bandwidth of 16 kHz. At 20.25 kbit/s, the transmission and reception
channels, each of 4 kHz, can be adjacent, resulting in a total bandwidth of 8 kHz.
When working with a QAM digital channel, the OPU-1 can integrate teleprotection signals in
the digital operation band.
Examples of transmission possibilities are summarized in FIGURE 1. In case of frequency
congestion, the OPU-1 can be equipped with additional filters to use different frequency
slots for the analog and the digital channels in the same line or, even, as is represented in
FIGURE 2, in independent lines.
The use of additional filters in a twin-channel analog terminal also allows the transmission
and reception bands of each channel to be non-adjacent.
The OPU-1 terminal can work with different line filters, depending on the backplane type.
If desired, as a solution for PLC networks with frequency congestion, the OPU-1 can
function as a High-Frequency teleprotection system. This functionality enables electrical
power utilities to transmit teleprotection commands between protection relays over
high-voltage lines in a single 4 kHz bandwidth, using 2 kHz for transmission and 2 kHz for
reception. This functionality implies a specific hardware architecture of the terminal.
OPU-1 terminals comply with the International Recommendation IEC 495, regarding PLC
equipment.
HF Teleprotection functionality meets the security and dependability requirements specified
in IEC 60834-1 Recommendation for the three types of teleprotection command schemes:
Permissive tripping schemes, Intertripping schemes (Direct or transfer tripping) and
Blocking protection schemes.