If the correct LEDs do not illuminate, there may be a problem in the transmit path of
the power mains coupling circuit of the UUT. Possible causes of a reduced transmit
signal level include:
•
Additional series impedance has been inadvertently added between the PLT-22
transceiver's coupling circuit and the mains connection.
•
The DC resistance of the series resonant inductor in the coupling circuit (L2 in
Chapter 4 coupling circuit figures) is too high.
•
The UUT contains a line fuse that has high series resistance.
•
A component of the wrong value has been inadvertently used in the UUT.
•
Inadequate analog power supply (
V
A
) voltage under conditions of full transmit
current loading.
Refer to the node checklist in Appendix B for more information about verifying the
UUT's design.
Receive Performance Verification
The receive performance verification procedure requires a software tool to measure
the number of uncorrupted packets received by the UUT. Packet error rate is then
calculated based on the number of packets sent and the number correctly received. A
utility program to monitor packet activity is described below, followed by a
description of the verification procedure.
Packet Error Measurement with Nodeutil
A DOS utility called
nodeutil.exe
will be used to measure packets correctly
received by the UUT. The Nodeutil software allows a PC to remotely query the UUT
and extract its status, including uncorrupted packets received by the node (stored in
every Neuron Chip). The
nodeutil.exe
utility is available free of charge from
Echelon’s Web site at www.echelon.com/toolbox.
Figure 7.9 illustrates the setup for the PC running the Nodeutil utility. The PC
should contain one of Echelon’s network adapters: PCLTA, PCNSS, or PCNSI
equipped with a PLM-21 or PLM-22 SMX transceiver. The adapter is connected to
the isolated power line via a PL-20 power line coupler.
The DOS driver for the network adapter,
ldvpclta.sys
, should be used by adding
the following line to the
config.sys
file on the PC:
device:c:\[path]\ldvpclta.sys [options]
The latest version of
ldvpclta.sys
is available from Echelon’s Web site. Refer to
the pertinent network adapter user's guide or detailed information about the driver
set-up and its options.
The
nodeutil.exe
program runs on the PC (under DOS) and accesses the UUT
over the power line. The verification procedure below describes how to use the
Nodeutil utility to access the UUT.
L
ON
W
ORKS
PLT-22 Transceiver User’s Guide
7-11
Summary of Contents for LONWORKS PLT-22
Page 6: ...iv Echelon...
Page 14: ...1 8 Introduction...
Page 67: ...LONWORKS PLT 22 Transceiver s User Guide 5 7 Figure 5 3 Capacitor Input Power Supply Schematic...
Page 92: ...6 10 Design and Test for Electromagnetic Compatibility...
Page 110: ...7 18 Communication Performance Verification...
Page 114: ...8 4 References...
Page 118: ...A 4 Appendix A...
