User's Manual

Elpro Technologies 450U-E Wireless Ethernet Modem & Device Server User Manual
Rev Version 1.4.0 www.cooperbussmann.com/wirelessresources 63
useful for determining if the communications get through after the first retry or it
continues to fail
TX Acknowledge messages
The percentage of time spent transmitting acknowledgment messages from the
modem and Broadcast messages.
Radio Hold off
The percentage of time that the radio has spent holding off from transmitting data,
possibly because the channel is busy.
RX to this radio
The percentage of time receiving messages specifically for the radio being
monitored, i.e. valid Elpro radio communication frames from other modems in the
system that are specifically addressed to this modem.
RX to other radios
The percentage of time receiving valid ELPRO messages addressed to other radios
within the system i.e. radios that maybe talking through a repeater and the host can
hear the message directly. Useful for determining how much radio traffic the
modem can hear that it may not need to.
RX acknowledgements
The percentage of time receiving acknowledge messages
RX Errors
The percentage of time dealing with radio receive error messages, i.e. corrupted
data, Data Collisions, etc.
By configuring the different chart options from above we can get a clear idea of the percentage of time spent handling
transmit and receive messages and/or the amount of other receive data that can be heard at the radio.
Configure what is to be logged from the drop down list, select a time interval, hanges and the charts will
then redraw the graphs and display below the settings. Each graph will display a percent channel utilisation using the
selected criteria and time interval (Seconds, Minutes or Hours).
Example One.
A good test would be to configure chart one to show ll data frames transmitted over the
radio link and chart two to show Rx valid data frames received from any source (ELPRO 450U-E
data frames). We can see from the results in Figure 71 - Custom Survey 1 that there is a large amount of data
being transmitted at the end of the chart and the receive data in chart two also shows a slight increase in traffic. From this
we can deduce that the radio itself or a device on the Ethernet network of the radio is transmitting a large amount of data.
If the charts showed an increased number of RX Frames instead of TX frames then this would indicate one or all of the
remote radios are transmitting excessive data and it would be advisable to perform the same TX/RX Custom survey on
these remote site/sites to determine the cause for the excessive data.
Figure 71 - Custom Survey 1