User's Manual

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WAM System User Guide

General Description

The Tehama WAM system consists of three device types to remotely monitor various

environmental and utility readings and provide the data to a central database or PC for formal

presentation and reporting. MDT/Sensor devices will be placed in all locations requiring local

monitoring of data. The MDT/Sensors will transmit time stamped data to a Base device, which

receives the data and forwards it to a Database computer through a variety of means (serial

port, USB Port, Ethernet). For MDT/Sensors that are out of range from the Base, Repeater

devices are added in appropriate locations to relay the data between MDT/Sensors and the

Base.

The system operates in the 865MHz (Europe/Asia) and 915Mhz (US) ISM bands using off-the-

shelf FSK RFIC radios. The system operates as a Frequency Hopper over 60 narrow band

frequency channels, incorporating a bidirectional communication link with Acknowledge (ACK)

messages to ensure all data reaches the Base. The MDT/Sensors are battery operated, bursting

data packets at pre-programmed times then shutting down to conserve battery life, estimated

to exceed 4 years. The Base and Repeater units are line powered.

With an average MDT/Sensor transmission rate of four per hour, a single Base can

accommodate many hundreds of MDT/Sensors. Through the use the ACK messages and local

memory in both the MDT/Sensors and Repeaters, the number of MDT/Sensors supported can

exceed a thousand. There is no limit to the number of repeaters, though an average

installation may require one Repeater for every 20-30 MDT/Sensors.

Figure 1: Typical System

WAM User's Guide.pages! 1 of 4

Summary of content (4 pages)

PAGE 1
WAM System User Guide General Description The Tehama WAM system consists of three device types to remotely monitor various environmental and utility readings and provide the data to a central database or PC for formal presentation and reporting. MDT/Sensor devices will be placed in all locations requiring local monitoring of data.
PAGE 2
A system consists of two or three types of hardware, and two pieces of software: • • • • • Database Software on a PC or Access Point Tehama Configuration Utility One Base Unit or Access Point A variable number of Sensors units, each with 2 AA batteries A variable number of Repeater units (optional, depending on size of installation) with external DC power supply. Warning NOTE: THE MANUFACTURER IS NOT RESPONSIBLE FOR ANY RADIO OR TV INTERFERENCE CAUSED BY UNAUTHORIZED MODIFICATIONS TO THIS EQUIPMENT.
PAGE 3
the Transmit Interval time. A value of 0 for this parameter will disable measurements in between the Transmit Interval. The units for this parameter are in seconds, with default set to 0. • Temperature Change, defined as a percentage change in the Thermistor resistance value (i.e. temperature) detected by the sensor. A Delta Temp alarm will be generated within the PC Software if a Sensor reading taken at a Measure Interval is more than Temperature Change percent from the prior Transmit Interval value.
PAGE 4
Once the initial Repeater placement is complete, the Sensor placement phase begins. Again the LED feedback can be used to verify that MDT/Sensors are communicating with the network. Additional repeaters can be placed in areas will minimal coverage. The Configuration Tool can also be used in the placement phase to provide more detailed information such as Link Quality and Signal Strength reading generated by MDT/Sensors and Repeaters.