User's Guide

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Tehama System (3rd Gen.) Installation Overview

General Description

The Tehama AMR 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. Metering Data Transceiver (MDT TW-111 and TW-112) devices will

be placed in all locations requiring local monitoring of data. The MDT devices will transmit time

stamped data to the DCAP device (DCAP TW-222), which receives the data and stores it in a

Database. The database information is available over Ethernet on the local LAN or the Internet.

For MDTs that are out of range from the DCAP, Repeater devices (RPT TW-222) are added in

appropriate locations to relay the data between MDTs and the DCAP.

The system operates in the 915MHz ISM bands using off-the-shelf Semtech RFIC radios. The

system operates either as a FHSS over 60 narrow band frequency channels, incorporating a

bidirectional communication link with Acknowledge (ACK) messages to ensure all data reaches

the DCAP or as a DTS non-hopping spread spectrum with 842kHz Bandwidth. The MDTs are

battery operated, bursting data packets at pre-programmed times then shutting down to conserve

battery life, estimated to exceed 5 years. The DCAP and Repeater units are line powered.

With a typical MDT transmission rate of one per hour (four per hour for Time of Use applications),

a single DCAP can accommodate up to 1000 MDTs. There is no limit to the number of repeaters,

though an average installation where MDTs are spread out in each living space will require one

Repeater for every 20-30 MDT/MDTs.

Figure 1: Typical System

Summary of content (6 pages)

PAGE 1
Tehama System (3rd Gen.) Installation Overview General Description The Tehama AMR 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. Metering Data Transceiver (MDT TW-111 and TW-112) devices will be placed in all locations requiring local monitoring of data.
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A system consists of two or three types of hardware, and a software program: • • • • A DCAP Unit A variable number of MDT units, each with 2 AA batteries A variable number of Repeater units (optional, depending on size of installation) with external DC power supply. Tehama Configuration Utility (CIT) running on a PC Warning NOTE: THE MANUFACTURER IS NOT RESPONSIBLE FOR ANY RADIO OR TV INTERFERENCE CAUSED BY UNAUTHORIZED MODIFICATIONS TO THIS EQUIPMENT.
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Tehama Configuration & Installation Tool (CIT) You should have received a copy of the Tehama Configuration and Installation Tool (CIT) software. If not, please contact support@tehamawireless.com and request the link. The CIT runs on a Windows based PC. More detailed information can be found in our training class materials or the Tehama QuickStart Guide available on our web site. The tool can be run on the PC either prior to or during a site installation, or when new MDTs are added to a system.
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MDT Configuration All MDT come from the factory with a default factory-set configuration; there is no user changeable setup of an MDT. It need only be connected to the meter and turned on. A number of different MDTs are available, our most popular being a single pulse input unit with a one-hour transmission interval. See our web site for other variations available. MDT and Repeater devices come from the factory in a powered off state.
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With the DCAP Unit powered up, the repeater backbone should next be placed. Start with units closer to the DCAP/AP, and use the LED feedback indication to verify the range is acceptable. At first just the minimum numbers of repeaters can be placed, and it is necessary that they be within range (solid 10 second LED “flash” when button pushed) for the backbone to be reliable.
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FCC/IC Compliance information for MDT TW-111, MDT TW-112, RPT TW-222 and DCAP TW-222 Users in the US The device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation Users in Canada This device complies with Industry Canada license-exempt RSS standard(s).