NMEA 2000® interface for electric drive systems

Connecting electric drive systems with the AC Drive Controllers Family SAC from Piktronik to the »fpCAN« via the »Communication Interface CI – NMEA 2000®«.

Hardware Requirements

Software Requirements

  • »Communication Interface CI – NMEA 2000®«: 1.10


Start Addresses
Inputfixed addresses 0x66, 0x67 (due to GD2 panel) *)
OutputPosition of the rotary coding switch * 16 for CAN1 (NMEA 2000®)

If the position of the rotary coding switch is “0” the default address is CAN_OUTPUT_ADDRESS = “128”
Functions of the DIP switch

Switching Unit 1 (SW1):

off125 kBaud on input (SAC / GD2) *)
on250 kBaud on input (SAC / GD2) *)

Switching Unit 2 (SW2):

offdrive type is unknown
ondrive type is 10 kW

*) GD2 is a display, control and battery monitoring unit from Piktronik.

Supported NMEA 2000® PGNs

ISO Acknowledgement 059392
ISO Request059904
ISO Transport Protocol, Data Transfer060160
ISO Transport Protocol, Conn. Management060416
ISO Address Claim060928
ISO Commanded Address065240
ISO Software Version065242
NMEA Request / Command / Acknowledge126208
PGN List (Transmit and Receive)126464
Product Information126996
Configuration Information126998
Engine Parameters, Rapid Update127488
Engine Parameters, Dynamik127489
DC Voltage / Current127551

Supported J1939 PGNs

EEC1, Electronic Engine Controller61444

PGNs in detail

PGN 127488 – Engine Parameters, Rapid Update
Engine Speedavailable, is sent
Engine Boost Pressurenot available (0xFFFF)
Engine Tilt/Trimnot available (0xFF)
PGN 127489 – Engine Parameters, Dynamic
Engine Oil Pressurenot available (0xFFFF)
Engine Oil TemperatureController Temperature (SAC)
Engine TemperatureDrive Temperature
Alternator Potentialnot available (0xFFFF)
Fuel Ratenot available (0xFFFF)
Total Engine Hoursnot available (0xFFFFFFFF)
Engine Coolant Pressurenot available (0xFFFF)
Fuel Pressurenot available (0xFFFF)
Engine Discrete Status 1available, is sent
Engine Discrete Status 2available, is sent
Percent Engine Load is calculated if the drive type is known
Percent Engine Torqueis calculated if the drive type is known
PGN 127751, DC Voltage / Current
DC VoltageBattery Voltage measured by the SAC
DC Currentaveraged DC Input Current of the SAC

The Voltage and especially the current may differ a little bit from the values shown by the GD2 display. This is because they are measured only by the SAC, whereas the GD2 display mesures via an external shunt over the whole system.
PGN 61444, EEC1, Electronic Engine Controller
Engine Loadis calculated if the drive type is known
Engine Speedavailable, is sent

Error messages

For a detailed description of the SAC Error Codes use the »User’s Manual for the AC Drive Controllers Family SAC« from Piktronik.

A detailed documentation of the NMEA 2000® »Engine Discrete Warning Status«, which is contained in PGN 127489, can be found in the original documentation that has to be bought from the NMEA website.

Since the »Engine Discrete Warning Status« of the NMEA 2000® PGN 127489 is defined for combustion engines, not all codes can be directly transferred to the SAC Error Codes, so the most similar ones are used.
SAC Error Code / MessageNMEA 2000® Error Message
(1) OVER CURRENTLow System Voltage
(2) OVER VOLTAGELow System Voltage
(3) UNDER VOLTAGE Low System Voltage
(7) OVER TEMPERATUREEngine Emergency Stop Mode, Engine Shutting Down
(8) UNDER TEMPERATUREEngine Emergency Stop Mode, Engine Shutting Down
(9) TEMPERATURE SENSOR ERROR (TEMP_FAIL)Engine Emergency Stop Mode, Engine Shutting Down
(21) MOTOR OVER TEMPERATURE (DRIVE_TEMP)Engine Emergency Stop Mode, Engine Shutting Down
(22) MOTOR TEMPERATURE SENSOR ERROR (DRIVE_TEMP_FAIL)Engine Emergency Stop Mode, Engine Shutting Down
NMEA2000_ENGINE_TEMPEngine Emergency Stop Mode, Engine Shutting Down

The SAC indicates whether the main relay is closed. In this case the SAC is active. If the SAC’s main relay is open, Engine Shutting Down is set on NMEA 2000®.
How does the Lowrance HDS 7 MFD evaluate the NMEA 2000® Error Messages?

The Lowrance HDS 7 MFD evaluates only whether the system is working properly (Engine Discrete Warning status = »0«) or a fault is present (Engine Warning Discrete status ! = »0«).

Multifunction Displays (MFDs)

The data of the »Communication Interface CI – NMEA 2000®« for electric drive systems can be displayed on current MFDs.

»Lowrance HDS 7«
»Garmin GPSMAP 722 Plus«
»Raymarine Axiom 7«