Specifications

Chapter 1 - Introduction
4 PL 3120/PL 3150/PL 3170 Power Line Smart Transceiver Data Boo
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Dual-Carrier Frequency Operation
The PL Smart Transceivers utilize a dual-carrier frequency signaling technology to provide superior communication
reliability in the face of interfering noise sources. In the case of acknowledged messaging, packets are initially transmitted
on the primary frequency and if an acknowledgement is not received the packet is retransmitted on the secondary
frequency. In the case of repeated messaging, packets are alternately transmitted on the primary and secondary
frequencies. In utility applications the primary and secondary communication frequencies lie within the A-band shown in
Figure 1.1. In non-utility applications, the primary communication frequency lies in the C-band shown in Figure 1.1 while
the secondary frequency actually lies in what is called the B-band in CENELEC nomenclature. Figure 1.2 illustrates how
the primary and secondary communications fit into the various frequency bands.
Figure 1.1 CENELEC Frequency Band Designations
Figure 1.2 Dual-Carrier Frequency Operation
20kHz 40kHz 60kHz 80kHz 100kHz 120kHz 140kHz 160kHz
Electricity Suppliers
"A"
"B"
"D"
Restricted
Band Designations
"C"
20kHz 40kHz 60kHz 80kHz 100kHz 120kHz 140kHz 160kHz
Restricted
A-Band
Communication
{
{
C-Band
Communication
Secondary
Frequency
Primary
Frequency
Secondary
Frequency
Primary
Frequency
Utility
Applications
Non-utility
Applications