Overview
The PLT-22 Power Line Transceiver provides a simple, cost-
effective method of adding L
ON
W
ORKS
power line technology
to any control system. Network data are broadcast through the
power mains, eliminating the need for dedicated wiring and
greatly reducing installation costs. A backward compatible
replacement for Echelon's popular PLT-21 Power Line
Transceiver, the PLT-22 transceiver includes several new features
to significantly improve communications reliability and lower
node cost.
A Global Product
The PLT-22 transceiver complies with FCC, Industry
Canada, Japan MPT, and European CENELEC EN50065-1
regulations for signaling in the 125kHz to 140kHz and 95kHz to
125kHz frequency bands. The transceiver implements the
CENELEC access protocol, which can be enabled or disabled by
the user. By incorporating the access protocol into the power line
transceiver, Echelon has eliminated the need for users to
independently develop the complex timing and access algorithms
mandated by the CENELEC EN50065-1 regulation.
The PLT-22 transceiver is also EIA 709.2 compliant.
Advanced Communications
Intermittent noise sources, impedance changes, and attenu-
ation make the power line a hostile signal path. The PLT-22
transceiver operates reliably in this harsh environment through a
novel Dual Carrier Frequency mode as well as custom digital
signal processing (DSP) which provides adaptive carrier and
data correlation, impulse noise cancellation, tone rejection,
and low overhead error correction. These innovations permit the
transceiver to operate reliably in the presence of consumer
electronics, power line intercoms, motor noise, electronic bal-
lasts, dimmers, and other typical sources of interference.
M A reliable power line communications solution that can be
used worldwide
M Backward compatible
1
replacement for Echelon's PLT-21
transceiver
M Dual Carrier Frequency mode and Digital Signal
Processing
M Communicates over virtually any AC or DC power mains
and un-powered twisted pair
M Uses low cost coupling circuits and power supplies
M FCC, Industry Canada, Japan MPT, EIA 709.2, and
European CENELEC EN50065-1 compliant
M Supports optional PLA-21 external amplifier
M Supports CENELEC A-band operation
Unsurpassed Performance
When the PLT-22 transceiver's dual carrier frequency mode
is activated, PLT-22-based nodes are able to communicate
even when their primary frequency range (125kHz140kHz) is
blocked by noise. With dual carrier frequency mode, a PLT-22
transceiver begins each transmission by sending packets in the
primary frequency range these packets may be received by
PLT-20, PLT-21, or PLT-22-based nodes. If impairments
prevent communication in this frequency range, the PLT-22 will
automatically switch to a secondary frequency range
(110kHz125kHz) in order to complete the transaction
with other PLT-22-based nodes.
The transceiver communicates at a raw bit rate of 5kbps.
With the CENELEC protocol disabled, the transceiver has
a maximum packet rate of 20 packets per second. With the
CENELEC protocol enabled, the transceiver has a maximum
packet rate of 18 packets per second. This high throughput
makes the transceiver well suited for residential, commercial,
and industrial automation applications.
The transceiver's power amplifier includes a selectable 3.5V
peak-to-peak (p-p) or 7V p-p mode for maximum
communication performance. The 1
output impedance and
1A p-p current capability of the amplifier allow it to drive
high output levels into low impedance circuits, while the highly
efficient design draws less total current than the previous trans-
ceivers. This increased output power improves signaling in all
applications and eliminates the expense of installing a phase
coupler in typical residential applications. The net cost savings
can be significant for home automation applications.
PLT-22 Power Line Transceiver
Model 50090-03
Powered Or Unpowered Lines
The transceiver uses a low cost external coupling
circuit and can communicate over virtually any AC or DC power
mains, as well as unpowered twisted pair. The PLT-22
transceiver can use all of the same coupling circuits as
the PLT-21 transceiver.
Inexpensive Power Supply
The PLT-22 transceiver is powered by user-supplied
+8.5 to +16VDC and +5VDC power supplies. The wide power
supply range is a key benefit when designing inexpensive power
supplies. If a battery-backed power supply is used, the transceiv-
er will continue signaling even during a power failure on the
power mains.
The PLT-22 transceiver incorporates a power management
feature that constantly monitors the status of the node's power
supply. If during transmission the power supply voltage falls
to a level that is insufficient to ensure reliable signaling, the
transceiver tells the Neuron
Chip to stop transmitting until the
power supply voltage rises to an acceptable level. This allows the
use of a power supply with 1/3 the current capacity otherwise
required (100mA versus 300mA). The net result is a reduction in
the size, cost, and thermal dissipation of the power supply. Power
management is especially useful for high volume, low cost
consumer products such as electrical switches, outlets, and
dimmers.
PLT-22 Power Line Node Block Diagram
Flexible And Backward Compatible
Supplied as a miniature, uncoated Single In-Line Package
(SIP), the PLT-22 transceiver can be mounted on or inside an
OEM product, directly adjacent to the Neuron Chip with which
it is used. When connected to an external crystal, the transceiver
can supply either a 1.25, 2.5, 5, or 10MHz clock signal to the
Neuron Chip, eliminating the need for a separate Neuron Chip
crystal (note: Dual Carrier Frequency mode requires a 2.5MHz
or higher Neuron chip clock).
With pin-for-pin compatibility with the PLT-20 and PLT-21
transceivers, the PLT-22 transceiver can be used in existing
designs and networks. At the same time, the PLT-22 provides
smaller package dimensions to more easily fit tight enclosures.
For commercial and industrial applications in high rises,
manufacturing plants, utility substations, and other large
facilities, the PLT-22 transceiver can be used with Echelon's
PLA-21 Power Line Amplifier. Capable of transmitting a 10V p-
p signal with 2A p-p current drive, the PLA-21 amplifier is ideal
for driving multiple phase coupling circuits, high attenuation
power circuits, and very low impedance loads near circuit break-
er panels and distribution transformers.
Helping You Succeed
To simplify the task of designing and commissioning
products using the PLT-22 transceiver, Echelon offers a
diagnostic tool, the PLCA-22 Power Line Communications
Analyzer, as well as a comprehensive range of development
tools, network interfaces, routers, and network services tools.
Technical support, design reviews and node verification for the
transceiver are all available through Echelon's LonSupport
TM
technical assistance program.
PLT-22 Power Line Transceiver Dimensions
Power
Supply
Neuron
3120 or
3150
D/A
Crystal
Coupling
Network
RX
Front
End
Line
Neutral/Earth
+5V
EPROM
(3150)
TX
AMP
VA
DSP
(PLT-22 Transceiver shown in shaded area)
NOTE: Solid lines are the PLT-22 outline; Dashed lines are the PLT-21 outline
Specifications
For operation in the 125kHz to 140kHz and 110kHz to 125kHz frequency ranges (C-band mode)
Function
Description
Microprocessor
Requires external Neuron Chip
2
Emissions compliance
Compliant with FCC, Industry Canada, Japan MPT, and CENELEC EN50065-1 specification for
low-voltage signaling
Safety agency recognition
U.L. 1950, cU.L. C22.2 No. 950, TV EN60950
Bit rate
5kbps raw bit rate
Communication technique
BPSK with DSP-enhanced receiver
Carrier frequencies
132kHz (primary) and 115kHz (secondary)
Input voltage
+8.5 to +16VDC @ 250mA, maximum transmit
+5VDC 5% @ 23mA, maximum
Connector pins
0.25mm (0.010
) x 0.4mm (0.016) on 1.8mm (0.071) centers
Operating temperature
-40 to +85C
Non-operating temperature
-40 to +85C
Operating humidity
25-90% RH @ 50 C, non-condensing
Non-operating humidity (24 hour)
95% RH @ 70 C, non-condensing
Dimensions
39mm L x 19.0mm H x 6mm W (approximately: 1.54
x 0.75 x 0.24)
Packaging
Uncoated single in-line package
Ordering Information
Product
Echelon Model Number
PLT-22 Power Line Transceiver
50090-03
L
ON
W
ORKS
PLT-22 Power Line
Transceiver User's Guide
078-0175-01 (order separately -- not shipped with product)
w w w . e c h e l o n . c o m
Copyright 2001-2002, Echelon Corporation. Echelon, LON, L
ON
W
ORKS
, L
ON
M
ARK
, LonBuilder, Nodebuilder, LonManager, Digital Home, LonTalk, Neuron, 3120, 3150, the L
ON
M
ARK
logo, and the Echelon logo are
trademarks of Echelon Corporation registered in the United States and other countries. LNS, the LNS Powered Logo, LonPoint, SMX, LonResponse, LONews, LonSupport, LonMaker, i.LON, Bringing the Internet to
Life, Open Systems Alliance, and the Open Systems Alliance logo are trademarks of Echelon Corporation. Other trademarks belong to their respective corporations.
Disclaimer
Neuron Chips, Free Topology Twisted Pair Transceiver Modules, and other OEM Products were not designed for use in equipment or systems which involve danger to human health or safety or a risk of property
damage and Echelon assumes no responsibility or liability for use of the Neuron Chips or Free Topology Twisted Pair Transceiver Modules in such applications. ECHELON MAKES AND YOU RECEIVE NO
WARRANTIES OR CONDITIONS, EXPRESS, IMPLIED, STATUTORY OR IN ANY COMMUNICATION WITH YOU, AND ECHELON SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTY OF MERCHANTABILITY
OR FITNESS FOR A PARTICULAR PURPOSE.
003-0307-01A
Notes:
1. The PLT-22 transceiver is a replacement for the PLT-21 transceiver, and can communicate with PLT-21 and PLT-20 transceivers.
2. Refer to the Neuron Chip Data Book from Motorola or Toshiba for Neuron Chip specifications and design information.
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