WM-E2S® Smart Metering Modem for PME-PMI® Electricity Meters

Document Specifications

This documentation was made to present the installation and configuration steps of the WM-E2S PME-PMI® electricity metering modem.

Chapter 1. Introduction

The WM-E2S 4G® is a modem, suitable for automated remote reading of electricity meters on the 4G LTE-based cellular network. It eliminates the need for manual readout of meter systems.

Wireless Communication

The modem can be ordered with different cellular module types:

• LTE Cat.4 / 3G / 2G module
• LTE Cat.1 module with 2G "fallback"
• LTE Cat.M / Cat.NB module with 2G "fallback"

All versions with a 2G mode or "fallback" feature communicate on the 2G network in case of LTE 4G outage or inaccessibility. The modem can be set to use specific networks (e.g., only LTE 4G or 3G) or the best available network (Auto mode). It can also use GSM-CSData connection by initiating CSData calls. The modem supports multi-operator SIM and roaming, offering a SIM-card and mobile operator independent solution. It operates in "Pull" mode, sending data transparently from the meter to the HES (smart metering center/server).

Design and Installation

This modem is developed for 3-phase PME-PMI® electricity meters (Itron® ACE6000, Landis+Gyr® ZMG416, and Enedis® NOI CPT-E36 meters). It connects to the meter via its RJ45 connection RS232 interface and is installable as an external modem using its 35mm DIN-rail adapter.

Operation Properties, Features

The modem reads actual and stored consumption values, event logs, load profile data, and can remotely modify meter parameters. It is accessed via the cellular network using the embedded Quectel® cellular module and sends data to the internet via an APN.

Power Source

The modem is powered by DC power (8-16V DC) from the meter via its RJ45 connection, receiving 10V DC for operation.

Supercapacitor

The device can include an internal supercapacitor to prevent intermittent power cuts and decrease power peaks, enabling operation during small power outages. After a few minutes of charging, it supports normal operation and data transmission. If the supercapacitor is exhausted, it needs recharging before the modem can restart and send data. A version without a supercapacitor is also available.

Connection / Configuration

The modem is configurable locally via its RS232 port (RJ45 connector), requiring a USB Dongle converter for PC connection. Remote configuration is possible via CSData call or LTE connection (TCP/UDP). APN, username, and password settings are configured based on information from the local mobile operator.

Chapter 1. Introduction (Continued)

Configuration Tool and Firmware

All settings are configurable using the WM-E Term® administration tool, which also offers an API for partners. The tool supports single device or group configuration, password protection, and user management. It requires a Windows® platform and is available in multiple languages, including French.

The WM-E Term® also facilitates safe firmware changes for modems, either locally (via RJ45) or remotely (via cellular connection).

Security

The modem performs hardware identification during firmware replacement and startup, preventing the installation or operation of third-party or modified firmware due to integrity and compatibility checks. The device's flash content is encrypted with AES-256. It uses a unique communication protocol with double checksums for data safety. The control port can be AES encrypted (optional). Configuration and communication passwords enhance security, and the firmware uses TLS protocol for maximum security.

Status and Notification

The modem continuously monitors the mobile network and communication health, sending status information like signal strength and QoS. It can send SMS alarm notifications and Last Gasp notifications, depending on the cellular network and mobile operator, provided SMS notifications are not disallowed.

Certification

The modem complies with the Radio Equipment Directive (ReD) standard 2014/53/EU (parts 3.a, 3.b, 3.c) and ReD Cybersecurity part 3.3(d). It is RoHS and CE certified.

Chapter 2. Connections

2.1 External Outfit

The external components of the modem are:

• 1 - Plastic transparent top cover
• 2 - DIN-rail adapter (for mounting)
• 3 - Alternative fixation lugs/holes
• 4 - Cover holders (loosen to open the cover)
• 5 - SMA / FME antenna connector (50 Ohms)
• 6 - Status LEDs
• 7 - Hinge (of top cover)

2.2 Internal Connections

The internal components of the modem are:

• 8 - SIM card slot (push left and spin up)
• 9 - Internal antenna wire (with U.FL – SMA / FME connection)
• 10 - RJ45 connector (for data and DC power)
• 11 - Jumper crossboard (for proper meter communication)
• 12 - Supercapacitor parts
• 13 - External connector (do not use)
• 14 - Holder of the top cover (part of modem enclosure)

Chapter 2. Connections (Continued)

2.3 Installation Steps

1. Ensure the device is not powered on, then remove the RJ45 connector (10).
2. The modem includes an anodized aluminum DIN-rail adapter (2) for 35mm DIN rails. The fixation part is on the bottom side of the modem enclosure.
3. To insert the SIM card, loosen the cover plastic lugs (3) and holders (4) on the bottom part (1b) of the enclosure. Pull and lift the semi-transparent top cover (1a) from the antenna connector side to open it, revealing the PCB (2).
4. The PCB is located on the left side.
5. Slide and open the plastic SIM card holder (8) by pushing from left to right, then lift it up.
6. Insert a replaceable, active SIM card (with APN access) into the SIM-holder (8). The chip should face down, with the cut edge oriented towards the antenna side.
7. Close the SIM holder (8) by pushing it from right to left until fastened. Then, close the PCB-side of the enclosure (semi-transparent plastic) back onto the white plastic part from left to right.
8. Ensure the internal antenna U.FL cable (black) is connected to the U.FL connector (9).
9. Close the top enclosure, ensuring correct positioning on the lugs and holders, until it clicks shut.
10. Connect the modem to the PME-PMI electricity meter (Itron®, Landis+Gyr®, or Enedis® type) using the provided 1m grey RJ45 cable connected to the RJ45 connector (10) for the RS232 interface.
11. Close the plastic cover (1) and install the modem by fixing the enclosure onto the 35mm DIN-rail.
12. Mount a LTE antenna. Use an SMA or FME-type antenna on the SMA connector (5), or an SMA-type antenna on an FME connector with an FME-to-SMA converter.
13. For configuration, connect the RJ45 cable to the modem's RJ45 port (10) and the other end to your computer via an RJ45-USB adapter (USB dongle). Refer to Chapter 3.1 for details.
14. Configure the modem using the WM-E Term® configuration software.
15. After configuration, disconnect the RJ45 cable from your computer (and USB Dongle) and connect it to the electricity meter's RS232 port via the modem's RJ45 port (10).
16. Remove the PME-PMI® meter's communication module plastic enclosure (bottom side) by releasing the screw from the top of the plastic cover, following the meter's installation manual.
17. Power on the meter. The connected modem will start due to the RJ45 connection power source. The modem will begin operation, and LED signals will indicate current activity. The modem is now ready for usage.

2.4 Description of the RJ45 Connector

Connect the provided RJ45-RJ45 (grey) cable to the modem's RJ45 communication interface (10). The PME-PMI (Itron® ACE6000, Landis & Gyr® ZMG416) meter's RJ45 connection pinout is shown below. Note that the modem side of the connector pinout is the opposite counterpart to the meter's side.

Chapter 2.5 Status LED Signals

If the WM-E2S PME-PMI® modem has been without power for an extended period, it requires charging before use. Charging takes approximately 2-5 minutes if the supercapacitor was exhausted.

Operation LED Signals - In Case of Charging Supercapacitors

During the charging of exhausted supercapacitors, only the green upper LED (LED 3) will flash quickly. This is the only active LED during charging. Wait until the device is fully charged.

Important: The LED numbers correspond to titles on the PCB: LED 3 (green, top), LED 1 (blue, middle), LED 2 (red, bottom).

Upon initial power-on during charging, the green LED (LED 3) flashes quickly. After a few minutes, it may go blank, then flash quickly again. When the green LED flashes slowly and other LEDs light up according to normal operation, the modem is fully charged and ready for configuration.

Operation LED Signals - In Case of Normal Operation

After the supercapacitors are charged, the following LED operations apply:

The operation and sequence of LED signals can be customized via the WM-E Term® configuration tool (Standard Meter Interface parameter group). The following LED functions can be defined:

• Not used
• GSM/GPRS status
• SIM status (wrong PIN flashing slow or without SIM)
• E-meter status
• Firmware status
• Network status and access technology
• Meter status with IEC polling
• AMM (IEC) client state (not usable here)

LED Status Descriptions

*The EI client is the transparent output TCP channel from the modem to the EI server.

LED Signaling During Firmware Update

During firmware upload, LEDs operate normally; there are no specific signals for FW refresh progress. After installation, all LEDs will be blank, and the modem will restart automatically with the new firmware. Upon startup, LED 3 flashes green for 15 seconds. The modem becomes available on its interfaces within 2-3 minutes. Afterward, LEDs operate as per normal behavior descriptions.

Chapter 2.6 Operation of the Modem

The complete readout and data sending mechanism to the HES centre, as well as configuration and maintenance tasks, are performed via defined paths. The system includes components like GSM MODEM POOL, TERMINAL SERVER, PRIVATE APN, DIGITAL CELLULAR RACK SYSTEM, GRID CONTROL SYSTEM, HEAD END SERVER, BACK OFFICE APPLICATIONS, and CELLULAR MODEMS connecting to C&I CUSTOMERS. Data flows from meters through cellular modems to the HES.

An alternative mode allows for automatic remote readout at predefined intervals or initiation based on events (e.g., meter cover removal, incoming SMS). In this mode, the modem connects to the mobile data network only during data transmission. Continuous cellular network connection is required for proper operation.

Chapter 2.7 LED Operation During CSD Call

Two operation types are available during a CSD call:

• a.) When the meter is read out / configured in transparent mode:
  • The GSM / GPRS status configured LED will be continuously lit during the CSD call.
  • The e-Meter status configured LED operates based on the CSD call status:
    • Flashes twice per second from connection attempt until closing the connection.
    • If the meter interface is not configured to 9600 baudrate, it will be continuously lit from connection attempt until closing the connection.
    • After connection closure, the LED switches off.
• b.) When modem configuration / firmware refresh is attempted:
  • The GSM / GPRS status configured LED will be continuously lit during the CSD call.
  • Other LEDs will not change their operation.

Chapter 3. Modem Configuration

3.1 Configuration

The modem must be configured using the WM-E Term® software by setting its parameters before normal operation. Before configuration, disconnect the meter<>modem RJ45 connection cable (14) from the meter's RS232/RS485 port (16). Connect the modem to your computer's USB port via the USB/RS232 DONGLE® adapter (17).

Important: The modem does not connect to the meter during configuration, so it cannot read parameter values through the RJ45 interface.

Configuration can be done via CSData call (using a 2G network) or through a mobile internet (TCP) connection, without needing to connect the modem to a PC. For USB connection, the power supply is provided by the converter board. Sensitive computers may require an external power supply.

For serial cable connection, configure COM port settings in Windows® (Start > Control Panel > Device Manager > Ports (COM and LTP)) as follows:

• Baud: 9600
• Databits: 8
• Parity: No
• Stopbits: 1
• Bandwidth control: no

Warning: If the COM port is not visible after connecting the device, install the FTDI VPC driver from http://www.ftdichip.com/Drivers/VCP.htm.

Proper modem communication requires configuring SIM settings (PIN code, APN, username, password) via WM-E Term® software. Adequate signal strength is necessary for successful communication.

If reading meter parameter values during PC-modem connection, select a different configuration port for the meter (e.g., TCP/IP or Optical) after the RJ45 configuration.

For newer firmware versions, a Communication password is mandatory. Contact sales for the default password. The password can be changed anytime via the menu icon.

The WM-E Term® program allows testing modem communication and executing AT-commands.

3.2 Configuring the Modem by WM-E Term®

Requires Microsoft .NET framework runtime environment. An APN/data package enabled SIM card is needed for configuration and testing. Configuration is possible without a SIM card, but the modem will restart periodically, and some features will be unavailable until the SIM card is inserted.

If the WM-E2S PME-PMI® modem was unpowered for a long time, it needs about 2-5 minutes to charge its supercapacitor before usage.

Download the WM-E Term® software from https://www.m2mserver.com/m2m-downloads/WM_ETerm_v1_4.zip. Extract and execute WM-ETerm.exe. The software supports user accounts and password changes. Refer to the WM-E Term® User Manual for details: https://m2mserver.com/m2m-downloads/WM-E-TERM_Manual_for_WM-E2S_WM-E2SL_V1_97B.pdf.

3.3 Parameter Configuration

General operation requires configuring cellular communication settings and SIM settings (APN, username, password, PIN, network usage method). Meter communication requires defining the communication port, RS232 settings (transparent mode, baudrate, data format, transmitting speed), and LED settings.

Main Settings:

1. Choose the Parameter read icon to retrieve current modem settings.
2. Select the APN Parameter group, click "Edit settings", enter the APN server name, and optionally the APN username and password. Click OK.
3. Select the M2M Parameter group, click "Edit settings", and enter the PORT number for Transparent (IEC) meter readout. Add this PORT number to the Configuration and firmware download for remote parameterization or firmware exchange.
4. If using a SIM PIN, select the Mobil network parameter group, enter the SIM PIN, and adjust the Frequency band (e.g., 4G only, LTE to 2G) or select a mobile network provider (auto/manual). Click OK.
5. For RS232 serial port and transparent settings, open the Trans. / NTA parameter group. Set Multi utility mode to transparent mode, Meter port baud rate to 9600, and Fixed 8N1 data format. Confirm with OK.
6. Open the RS485 meter interface parameter group and set RS485 mode to Disable. Click OK.
7. After completing settings, use the Parameter write icon to send changes to the modem. The configuration process status is shown at the bottom of the screen. The modem will restart with new settings.

Further Options:

• Refine modem handling via the Watchdog parameter group.
• Save current configuration via File/Save menu item for later distribution.
• Perform firmware refresh via the Devices menu, Single Firmware refresh item, selecting the appropriate firmware file (.DWL).

Attention: Inquire about the latest firmware availability.

3.4 Configuring from CSD Connection

If the modem restarts due to incorrect configuration, it can be accessed via a CSD call. Fine-tuning is possible in WM-E Term® software by setting the PDP connection delay in the APN parameter group.

Chapter 3.5 Data Control Direction (DCD) Feature

For PME-PMI, Itron® SL7000 meters (via RS232), the DCD feature declares data control direction. Configure this in the RS485 interface settings parameter group. This is valid for the RS232 port.

DCD Parameter Values:

• Fix 0 (provides logical 0 value for the connected meter)
• Fix 1 (provides logical 1 value for the connected meter)
• Standard
• Inverted (opposite direction)

Chapter 3.6 Automatic Network Reconnection

If the mobile network provider disconnects the modem due to inactivity, parameters can be set for automatic and periodical connection rebuild. If the provider sends a message indicating data connection loss, the connection will be restored automatically. If no message is sent, two workarounds are available:

• a.) Active Mode - Use Periodical Ping: Set ping parameters in the Watchdog parameter group (Ping IP-address, Number of ping retries, Ping wait-time, Wait-time). If no ping response, it reconnects to the network after the interval specified in the "Seconds, GPRS connection closed and restored after this time" parameter.

Attention: Frequent ping usage increases data traffic but improves chances of remaining on the cellular network.

• b.) Passive Mode - Set Connection Retry (if not using ping): Use the Watchdog parameter group's "Seconds, gprs connection closed and restored after this time" parameter. This defines how long the modem waits before attempting to reconnect after a network drop. Consult your mobile provider for offered settings.

Attention: With low data traffic and no ping configured, the device may stay offline longer. Setting this parameter too low can cause frequent reconnections. Never set it lower than recommended by your mobile service provider.

Chapter 3.7 Signal Strength

Check cellular network signal strength in the WM-E Term® software (Device Information menu or icon). Current status information updates upon completion. Aim for an RSSI value that is at least yellow (average signal strength) or green (better).

Antenna position can be adjusted while monitoring signal strength; re-readout is needed for refresh.

Chapter 3.8 Power Outage Management

The firmware supports the LastGASP feature, allowing the modem to operate for a short time (minutes) using its supercapacitor during power outages. Upon detecting loss of mains/input power, the modem generates a "POWER LOST" event and sends an SMS to a configured phone number. Upon recovery, it sends a "POWER RETURN" message via SMS. LastGASP message settings are enabled via the WM-E Term® application in the AMM (IEC) parameter group.

Chapter 3.9 Restart the Modem

There is no direct restart option in WM-E Term®. To restart the modem:

1. Choose any parameter from the read-out values.
2. Change a parameter value.
3. Click the Save button.
4. Send settings to the modem using the Parameters Write icon.
5. The modem will restart upon completion.
6. The restart is indicated by LED 3 flashing green for 15 seconds. The modem becomes available on its interfaces within 2-3 minutes.
7. Afterward, LEDs operate according to normal behavior descriptions.

Chapter 3.10 Two Meter Readout Ports

Every WM-E modem has two ports for meter communication, configuration, and FW updates, which can be configured by priority. The first port, the Utility communication port (Primary), is used for meter readout and configuration and has higher priority. It overrides the secondary port's operation; for example, if the meter is being read via the primary port, the secondary port's operation (e.g., meter reading) will be suspended until the primary port's readout is finished. This prioritization does not affect firmware updates or configuration processes.

The second port, the Customer communication port (Secondary), is used with lower priority for meter communication, configuration, and FW updates. The two ports should be set to different port numbers. This feature is configurable in WM-E Term® (Standard settings or Advanced settings in the M2M parameter group) and is available in firmware v5.3.4.1 or newer.

Chapter 3.11 Automatic Protocol Detect and Switch

The Data format for meters value (E-Meter serial port) can be configured in WM-E Term® (Standard settings or Advanced settings in the Transp. / NTA parameter group). In addition to standard formats (7E1, 8N1, 7O1, 7N2, 8E1, 8O1, 8N2), the 'Auto' mode setting is available. In 'Auto' mode, the firmware checks the first incoming data packet. If it detects the IEC protocol, the modem switches to data mode 7E1 for the meter; otherwise, it remains in 8N1 mode. This feature is available in firmware v5.3.4.1 or newer.

Chapter 4. AT Command Settings - Description

4.1 General Information About the Commands

This section details standard Hayes™ AT commands for manual modem programming via any terminal application. Commands are case-insensitive and accepted in N81 or E71 format. Before using AT commands, declare the modem interface and GPRS settings. AT commands and parameter values are separated by semicolons (e.g., Command;answer;timeout(msec)).

Minimal modem configuration settings for connecting an Itron® meter:

• AT+0: Enables 9600,8,n,1 operation.
• AT&W: Saves the settings.

4.2 AT Command Set

AT+ commands can be used individually.

Chapter 4. AT Command Settings - Description (Continued)

4.3 Commands Which Can Be Used Only for the Local Interface

4.4 Modem Result Codes

4.5 Configure the TCP/IP (GPRS) Connection

Check modem response by executing the AT+I command. The following commands are necessary for TCP/IP (GPRS) connection settings:

Chapter 5. Support

For technical questions regarding usage, contact WM Systems:

• Email: support@m2mserver.com
• Phone: +36 20 333-1111

5.1 Support

The product has an identification void with important product-related information for support. Warning: Damaging or removing the void sticker voids the product guarantee.

Online product support is available at: https://www.m2mserver.com/en/support/

5.2 Product Support

Documents and information related to the product are available at: https://m2mserver.com/en/product/wm-e2s-modem-for-pme-pmi-meters/

Chapter 6. Legal Notice

©2025. WM Systems LLC. The text and illustrations in this document are copyrighted. Copying, usage, replication, or publication of the original document or its parts requires explicit agreement and permission from WM Systems LLC.

The figures in this document are illustrative and may differ from the actual appearance.

WM Systems LLC. assumes no responsibility for text inaccuracies in this document. Information presented is subject to change without notice. Printed information is for informative purposes only; contact WM Systems for further details.

Warning: Any fault or error during software upload/refresh may lead to device breakdown. Contact WM Systems specialists in such cases.