User's Manual
PAC Configuration Manual
Wireless Matrix Corporation #102, 1530 - 27 Avenue NE Page 8 of 62
Document # xxx-xxx-xxx Calgary, AB, Canada T2E 7S6
2002.02.01 Ph. 403.250.3949 Fax 403.250.8163 www.wrx-ca.com
1 INTRODUCTION
The terrestrial processor assisted connector (TPAC) is a device that is an interface between
an end-device and the Wireless Matrix IP Anywhere service. A terrestrial communications
medium is an integral part of the TPAC. The term “terrestrial” is used to differentiate the
communication network from a “space” (satellite) network. Examples of terrestrial networks
are the public switched telephone network (PSTN), public cell-based wireless packet data
networks (DataTAC, Mobitex, GPRS, CDPD), public wired packet data networks (Datapac,
the Internet) and private wired and wireless networks.
The TPAC collects data from an end-device such as an RTU or PLC and passes the data to IP
Anywhere using the terrestrial data network. The TPAC can communicate with numerous
end-devices in the device’s native protocol via an RS-232 or RS-485 serial communication
link. RS-422 and other physical layers are supported with converters. The TPAC provides
timed reports, reports by exception and reports on demand.
An I/O point is a measured or stored value in an end-device. The TPAC can read an I/O
point using the device communications protocol. An I/O point can also be internal to the
TPAC or signals on the general-purpose I/O lines on the TPAC. The TPAC stores a list of
I/O points that it needs to access.
1.1 TPAC Features
• The TPAC can communicate with an end device using its native protocol.
• The TPAC has an integral RIM DataTAC transceiver for communications.
• The TPAC can report data on a scheduled interval, real time events or on demand.
• The TPAC responds to a remote “DEMAND POLL” request by reading the current
I/O values from the remote site and sending updated values to the GDN.
• The I/O points and alarm set points can be edited remotely over the communications
network.
• The TPAC can store I/O points in multiple poll sets. Each poll set has its own report
time and interval and can be adjusted remotely.
• The TPAC can minimize power consumption by entering a low power “sleep” mode.
• The TPAC can poll RS-232 and RS485 serial end-devices for I/O points.
• The TPAC can interface directly to transmitters (1-5 volts, 4-20 mA, digital) for I/O.
• During a poll operation the TPAC read the I/O points from a specified poll-set. The
unit will send a report to IP Anywhere if:
• A report is scheduled
• An analog I/O value crosses the preset alarm limits
• An analog I/O value changes by more than a preset dead band
• A discrete value either changes state or transitions to a specific state