Gateway V4 + CARMEN DSP
Wireless M-Bus Gateway V4 with the CARMEN DSP add-on.
Description
Gateway for remote reading of Endress+Hauser CARMEN sensors. CARMEN (Capacitive And Resistive Measurement ENdress+Hauser) is a digital signal processor (DSP) integrated into pressure sensors. The gateway reads pressure and temperature measurement values from the sensor and forwards them via NB-IoT, LTE-M mobile radio or LoRaWAN to the Internet. Suitable for indoor and weather-protected outdoor installation.
Features
All Gateway V4 Series platform features plus:
- Reads pressure and temperature values from an Endress+Hauser CARMEN sensor via its DSP interface (UART)
Product Components
- Firmware
- app-nrf91-origin · Firmware updates
- Housing
- LoCube — 122 × 82 × 55 mm
- Power supply
- Battery 38 Ah (Li-SOCl₂, 3.6 V) · External 12 V DC or 230 V AC available
- Optional accessories
- External antenna (SMA) · IP68 encapsulation · LoCube wall mounting kit · Pole mounting kit
Product Identification
- Name: Wireless M-Bus Gateway V4 CARMEN
- Type: LOB-GW4-Carmen
- MPN / Ordering code: n/a (on request, contact sales@lobaro.de)
Accessories
| Accessory | Notes |
|---|---|
| LoCube Wall Mount | Optional — wall or horizontal pipe |
| LoCube Mast Mount | Metal bracket for vertical pole / mast mounting |
| USB Config Adapter | For local configuration, diagnostics, and firmware updates |
Datasheet & Quickstart
Please contact our sales team.
LED Signal Patterns
The device uses the standard V4 LED signal patterns. See LED Signal Patterns for the full reference.
Battery Lifetime Estimator
Please contact our sales team.
Configuration
The device is shipped with default configuration parameters. Local changes can be made via the config port using the USB Config Adapter and the Lobaro Config Tool.
For step-by-step instructions, see the Configuration Methods guides:
- 🔌 Local Config via USB — connect directly to the device
- 📡 Remote Config via CoAP — over NB-IoT / LTE-M via Lobaro Platform
- 📻 Remote Config via LoRaWAN — via LoRaWAN downlink
- 🔗 Remote Config via MQTT — for 3rd party MQTT backends
Custom factory configuration is available on request — devices can be pre-configured at production for your specific deployment. Contact sales@lobaro.de when ordering.
Default Values are the firmware defaults. Depending on the application the device may be delivered with different settings, see chapter below.
Configuration Parameters
This product runs the app-nrf91-origin firmware. To avoid duplication, the parameters are documented centrally with the firmware component and are not repeated here:
- Common firmware parameters — general, wireless M-Bus, LTE and LoRaWAN settings shared by all V4 gateways
Application specific non-default values
The following parameters are configured in production to align with the application settings:
| Name | Description | Value |
|---|---|---|
| carmenUartSpeed | Data rate of the UART (8N1, no hardware flow control). Cannot be changed by the user at the moment | 57600 |
| carmenCommand | Comma-separated list of commands executed at startup | soft_reset,read_typeplate,soft_reset,read_frame,stop_dsp |
Firmware Updates
The latest firmware can be found here:
- Download latest firmware
-
For further information on how to update the device, refer to: Firmware Update.
A remote firmware update over LoRaWAN is currently not possible.
LoRaWAN Uplink Formats
- LoRaWAN Protocol — Status Packet (Port 1) and general uplink formats
Pressure & Temperature Uplink
Measurement values are sent as the following data package:
| Byte(s) | Field | Type | Description |
|---|---|---|---|
| 1 | 0x00 | uint8 | Message type |
| 2–6 | Timestamp | 5 byte | Measurement timestamp |
| 7–10 | Pressure | IEEE float | Pressure value |
| 11–14 | Temperature | IEEE float | Temperature value |
| 15–16 | Voltage | uint16 | Battery / supply voltage |
Cellular Uplink (LTE)
Cellular uplink uses CoAP (with the Lobaro IoT Platform) or MQTT for third-party integration. The protocol details are documented centrally with the firmware:
The CoAP implementation details are not publicly disclosed and are intended for use exclusively with the Lobaro IoT Platform. If MQTT is not an option, please contact Lobaro directly.
Uplink Parser
A production-ready parser for the uplinks of this device is implemented within the Lobaro Platform. It covers the wireless M-Bus telegrams (including split telegram reassembly where applicable, AES-128 decryption for encrypted telegrams, and OMS-compliant data interpretation) as well as the add-on data of the respective variant, for example Modbus responses or sensor values.
Customers using the Lobaro Platform can utilize this parser directly as part of the platform processing pipeline.
If you are operating a Lobaro Gateway without using the Lobaro Platform, we can provide restricted platform access upon request. This allows you to inspect the parser behavior and use it as a technical reference for your own backend implementation.
Please contact our support team if you require access or further integration details.
Declaration of Conformity
 | Download CE declaration of conformity |