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Supported devices — NMEA 2000 gateway
Every device on an NMEA 2000 backbone announces itself when it joins: a device class, a function within that class, and a manufacturer code. That announcement is the whole of what this gateway matches on. It does not read model names, it does not read firmware versions, and there is nothing to declare by hand.
The practical consequence is worth stating plainly: support is by family, not by model. Any Victron device that announces itself as a battery charger is translated, whatever it is called in the catalogue; and a charger from a manufacturer not in this table is not translated, however similar it is.
The table
| Type | Function | The equipment announces itself as | Manufacturer | Model | Firmware version |
|---|---|---|---|---|---|
| Battery | 5 | class 35 electrical generation, function 170 battery | Victron (0x166) or MG (0x488) | any — the gateway then sorts BMS from shunt by itself, see below | not read |
| Converter — inverter / charger | 6 | class 35, function 153 AC main | Victron (0x166) | any | not read |
| Converter — DC/AC | 6 | class 35, function 162 DC/AC converter | Victron (0x166) | any | not read |
| Solar charger | 10 | class 35, function 160 battery charger | Victron (0x166) | any | not read |
| Alternator | 27 | class 35, function 141 DC generator | Arco Zeus (0x57B) | any | not read |
| Battery concentrator | 30 | class 120 display, function 130 display | Victron (0x166) | any — in practice the GX device of the installation | not read |
| Bow thruster | 32 | class 50 propulsion, function 145 thruster engine | Vetus / Maxwell (0x41D) | any | not read |
"Type" is the MUXEN function code the translated device appears under on the boat — the <function> in the Brain's device/<function>/<instance>/… topics. How the instance is chosen is in Reference — NMEA 2000 gateway.
One more device is recognised but never appears on its own: a Victron AC output (class 35, function 154) attaches to the inverter it belongs to and supplies its AC voltage and current. It is not a MUXEN device of its own and has no function code.
Batteries: BMS or shunt
Both a battery BMS and a plain current shunt announce themselves as a battery, and the gateway cannot tell them apart from the announcement. It settles it by asking: it polls the BMS register, and
- a device that answers is a BMS — state of charge, cell minimum and maximum, charge and discharge limits, charge request;
- a device that refuses three polls in a row is recorded as a shunt and is no longer asked — voltage, current and temperature only.
Three refusals rather than one, so that a BMS still starting up is not mistaken for a shunt. Until it has answered once, a battery is neither: it publishes what it broadcasts and nothing more.
What the gateway announces about itself
When it acts as battery concentrator — that is, as the charge master for a Victron system — the gateway answers the Victron identification registers with fixed values compiled into the firmware:
| Register | Value |
|---|---|
| Product ID | 0xFFA39100 |
| Firmware version | 0x0131FF00 |
| UDF version | 0x000200FF |
These are what the Victron installation sees, and they do not change with the CanCan's own software version. The CanCan's real identity — product ID, hardware ID, software version — is read over the MUXEN side with muxen-uds, not from here.
What is not recognised
- Any device of a supported class and function but another manufacturer — a Mastervolt charger, a Lithionics BMS.
- Solar panels announcing themselves as panels (function 142) rather than as chargers.
- Everything outside energy and the bow thruster: navigation instruments, wind, depth, heading, position, engines, tanks, displays other than a Victron GX.
An unrecognised device is left strictly alone. It keeps working on its own backbone; it simply does not appear on the boat.