S7 NMEA data converter

MasterCAN S7 NMEA data converter is a tool for transforming broadcasted data from DFM S7 and DFM Marine S7 wireless (BLE) flow meters into NMEA 2000-standard messages.

The data converter is used in telematics and fuel monitoring systems of technical and passenger ships equipped with NMEA2000 electronics.


Messages converted by MasterCAN S7 NMEA to standard onboard NMEA-devices:

  • instant fuel consumption;
  • total operating time of consumers;
  • fuel temperature.

MasterCAN S7 NMEA is certified by the National Marine Electronics Association.

Application of MasterCAN S7 NMEA in water transport telematics

MasterCAN S7 NMEA converters are used with DFM fuel flow meters installed on engines, diesel generators, boilers and booster units of boats, tugs, ferries, bulk carriers, dredgers and other types of watercrafts.

When the MasterCAN S7 NMEA and DFM flow meter are integrated into the vessel’s telematics system, the onshore team gets valuable data for identifying unusual fuel usage values, detecting possible engine and genset malfunctions, and plan fuel system maintenance.

Integration of flow meters with ship displays via NMEA2000

Transferring information from DFM flow meters to standard displays via the NMEA-2000 interface helps the ship’s crew to:

  1. measure fuel consumption of propulsion engines, marine diesel generators and other fuel consumers,
  2. keep count of the duration of engines, diesel generators and boilers operation,
  3. calculate ship’s cruising range and plan bunkering.

Obtained information is used to ensure normal operation of propulsion engines, diesel generator sets, boiler equipment, as well as filling out reports on ship’s operation.

Data from DFM flowmeters on OEM display via NMEA-2000 interface

How S7 NMEA converter and fuel flow meters operate in NMEA2000 bus

Operation principle of S7 NMEA converter and flow meters in the ship's NMEA2000 bus

MasterCAN S7 NMEA receives wireless signal via BLE (Bluetooth Low Energy, Bluetooth 4.X) channel from one or two fuel flow meters, converts and transmits messages according to the NMEA 2000 standard. The data can be displayed on the ship’s on-board NMEA display, and also sent to a telematics server if a telematics unit (GPS tracker, black box) is installed on the ship.

In case of differential fuel consumption measurement, MasterCAN S7 NMEA calculates the difference between instant fuel rate values in fuel supply and return lines, and generates corresponding NMEA message. Thus, the converter sends the already calculated value of differential fuel consumption, which does not require further processing.

Differential fuel consumption control with MasterCAN S7 NMEA and DFM S7

Mutual calibration of the installed flowmeters is not required, because each flowmeter is equipped with a processor and calculates the instantaneous flow rate in the fuel line independently.

MasterCAN S7 NMEA converter configuration

MasterCAN S7 NMEA data converter is configured using the Service S7 NMEA mobile application and Android device (smartphone or tablet). The Service S7 NMEA application is available for download from Google Play.

The mobile application allows:

  • Configuring the MasterCAN S7 NMEA converter – select the baud rate, change the network address.
  • Linking one or two flow meters to the converter using S7 Technology (Bluetooth Low Energy).
  • Assigning Master/Slave status to flow meters when calculating differential fuel consumption.


Input interface Bluetooth 4.2
Output interface CAN (NMEA 2000)
Maximum current consumption at supply voltage 12/24 V 130/70 mA
Operating temperature -40 … +85 °С
Ingress Protection Code IP 68
Weight, max 0.2 kg
Dimensions (L*W*H) 128*70*52 mm
Interface cable length 940 mm
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