Envco – Environmental Equipment

The M2w endpoint radios are approved to operate in the unlicensed 900MHz ISM band (902 to 928 MHz) under FCC section 15.247. No FCC licensing is required for the operation of the M2 radios or G2 Mobile/G2 Net systems.

The M2w utilizes an efficient, power-saving one-way mode for standard meter reading operations. In this mode, the M2w transmits its standard data packet (ID, Register Read, Data Flags, CRC) once every three to ten seconds (based on installation/location). The M2w data packet is received by either the R2 or NRD devices in the mobile or fixed system.

For the more complex communications, such as remote configuration or datalogging, the M2w moves to a two-way mode. This mode is initiated by the mobile or network device. During two-way communication, the M2w handshakes with the R2 devices to transfer and verify data.

Data Security and Integrity
All M2w one-way and two-way data is verified with a 24-bit CRC check. This CRC check ensures that there is no data corruption during any segment of the communication due to interference or collisions. Furthermore, the M2w data packet structure is a custom, proprietary format transmitted in an encoded format.

RF Performance
RF performance, typically evaluated as reception distance or reading speed, is a complicated topic. Reception distance and reading speed are impacted by the transceiver sensitivity, antennas, installation location, weather, etc. However, the M2w employs a simple, one-way mode for reading. It is a simple, efficient transmission only. Therefore, the transfer of the basic data does not require the sync-up between the endpoint and the transceiver. This simplicity bypasses in less retries, rejections, collisions, etc. and results in better distance and driving speeds.

Register Compatibility
The M2w Endpoint Radio can interface to virtually any electronic water meter register – encoded, switch or pulse. A current compatibility chart is available. This flexibility ensures that the city is not boxed in with a specific vendor or technology.

Installation
The M2w Endpoint Radio comes in a single model which is suitable for any environment or location. The unit can be fully submersed and has UV protection for outdoor mounting. The unit can be ordered in a clear or smoke colored plastic. The M2w is rated for operation from -20oF to +140oF (-20oC to +85oC)

The M2w Endpoint Radio does not require any special installation to meet FCC guidelines. The M2w does not require holes, above-lid installation or plastic lids in pits or vaults, although some optimized installations must be considered for fixed network operations.

Wiring
All M2w wiring connections are handled with the defacto-standard for encoded registers:
Red – Clk/Power
Green – Data
Black – Ground
Only three or two wires are required for any encoded, switch or pulse.

Configuration
The M2w Endpoint Radio can be configured locally with a T2 Field PDA or remotely with the G2 Mobile system. Configuration consists of three primary groups of settings:

Meter Settings: This group of settings configures the M2w for the type of register input, encoder/switch/pulse resolution and value, ID type plus some additional informational details such as meter type, size and units.
Transmit Settings: This group of settings configures the M2w for the transmission interval, scaling and ID options
Log Settings: This group of settings configures the M2w for the data functions: Datalogging, leak detection, conservation, high usage, zero usage, backflow.

Datalogging
The M2w Endpoint Radio can store up to 16,000 datapoints. The duration of this datalog is dependent upon the query interval as shown in the attached image

The M2w’s internal datalog can be downloaded at anytime with a handheld/PDA, the G2 mobile system or in certain G2 Net configurations. The download of data is almost instantaneous, with a rule of thumb of 1 second per 1000 points of data. The M2w’s internal datalog is used in most of the data function algorithms as described below.

Data Functions
The M2w radio endpoint includes the following data functions:
• Conservation Monitoring
• Leak Detection
• High Usage Monitoring
• Zero Usage Detection
• Backflow Detection
• Maintenance Flags

All of these functions are configurable to match the type of service (residential, commercial, industrial), size, resolution, season, etc.

Each M2w radio endpoint runs these algorithms 24/7/365. If any condition is met, the M2w sets a flag for the condition which is then transmitted with the standard reading transmission packet. Either the G2 Mobile or G2 Net system, upon receiving the transmission, displays a specific icon to indicate the condition to the user. The user can then request a detailed datalog to investigate the specific consumption pattern.

M2 Radio Specifications
Model: M2w for Water Meters
Description The M2w Endpoint Radio is a spread spectrum utility radio with universal compatibility to industry water meter registers.

RF Specifications
FCC Compliance: Part 15.247 Unlicensed
Frequencies: 902 to 928 MHz

Electrical Specifications
Battery: 3.6V 19.0 Ahr D-Cell
Battery Type: Lithium Thionyl Chloride
Max Power: 0.22W
Replaceable: Yes
Disposal: By qualified recycler

Physical Specifications
Weight : 1.15 lb (0.52 kg)
Dimensions: 4.3 W x 4.8 H x 2.0 D inches (110 W x 123 H x 52 D mm)
Enclosure rating: Fully submersible
Temperature Rating: -40 to 140 oF (-40 to 60 oC)
Enclosure: UV-protected polycarbonate
Color: Clear or Smoke

Wiring
Register wiring: 22 gage
Color Code: Red – Clk/Power, Green – Data, Black – Ground
Termination: Gelcap

Installation
Wall/post mount: Built-in mounted ears
Register mount: Optional bracket with cable compartment

Communication
Local: Short-range IR
Remote: RF Channel

Use with the G2 Mobile system which utilizes a Durabook laptop computer for the user interface and data storage platform. This laptop is selected for its performance and hardened physical specifications. The Durabook is pre-loaded with all G2 Mobile software and pre-tested with the R2m Mobile Transceiver and GPS receiver prior to delivery.

Or a network can be set up using these devices.
The SNC SubNet Controller serves as a data management hub for a sub-network of endpoints radios, NRD relays and R2n transceivers. The SNC controls network traffic commands to the subnet and collects and stores data from all endpoints in the subnet.

R2n Network Transceiver
The R2n is a highly sensitive 900 MHz Spread Spectrum network transceiver. It serves as a data collector for any radio endpoints in proximity and also as a router for AMR network traffic.

NRD Network Relay
The NRD is a one-way 900 MHz Spread Spectrum network relay. It serves as a data relay for any radio endpoints in proximity.

G2 Central Host
The G2 Central Host is a PC-based user interface for network control, diagnostics, data collection, billing system interface and reporting.

Ordering Information
M2w: Universal Endpoint Radio for Water Meters
M2g: Universal Endpoint Radio for Gas Meters
M2e: Embedded Endpoint Radio for Landis & Gyr Focus kWh electric meter