Is it possible to change the data instance for BMW-712 using the Yacht Devices Can Log Viewer or do i have to use root menu and command lines on Cerbo gx?
asked
How to change the data instance for BMV-712 in NMEA2000?
I am also having difficulties with this, I have two BMV-712 devices and despite modifying the instance number via Maretron N2K Analyzer the instance within the devices remain at 0.
Are we able to directly change the device instance number?
See images showing PGN's being transmitted.
Hi.
I am still working to solve this and will try to change this with command lines via color gx later today. I don't have Maretron or Actisence. Have you seen this instruction using Maretron?https://www.victronenergy.com/live/ve.can:changing_nmea2000_instances
Hi Jonnys, yes I have seen the instructions on howto update the instances, that is how I changed the instance nuber to 50 on the example shown in the clip - the actual data being transmitted shows the deviceis still transmitting as Battery Instance 0 for the primary battery and as 1 for the start battery. This occurs for both units. I have had to disconnect the second BMV as my generator start is monitoring instance 0 SOC and this way the system can see two of them.
The unique instance changes the Device Instance (lower + upper) in the ISO address claim message. Unique instance = 8 * high + low, so that is changed.
Do make sure you run at least v2.51!
Hi Jeroen, my Venus GX is running v2.52, I am not sure what you mean by the changing of high and low and that high plus low = 8. Can you explain in more detail?
@Greg Ireland, hi Greg. In N2KAnalyser, add the column Device instance (I do not see it in your screenshots). The device instances for each identical piece of equipment needs to differ from each other. This also counts for your tank sensors (see other post), which I do not see in these screenshots, which might explain why they do not show on VRM/Remote console.
There should be no need to change data instances on the CAN-bus. From the specs: "Data instances shall be unique in the same PGNs transmitted by a device. Data instances shall not be
globally unique on the network. Field programmability shall be implemented through the use of
PGN 126208, Write Fields Group Function."
Preferably, don't change them. It is a workaround for broken implementation. If the Yacht Devices Can Log Viewer can change them depends if mentioned write fields is implemented, which I doubt. The Maretron doesn't support it as far as I know. But the best solution is to just fix setups which incorrectly assume network wide unique data instances.
Hi and thanks for the reply. The problem I am experiencing is that YD web gauges switch on measurements between two battery banks. I have three battery banks REC-bms + two battery banks connected to the BMW712. This is what I got from the YD engineer: Is it wrong?
Battery banks appear in the NMEA 2000 network under the same battery instance. Web Gauges is capable to display data from 16 different batteries but they must have different NMEA 2000 battery instance settings. Victron gives the following instructions on changing N2K instances (IMPORTANT: you have to change data instances, not device or system instances):
The text is not wrong, that is apparently what they do. It is not conform NMEA 2000 specs though.
I agree. The new YD gateway has a number of problems with integration. Experience the web gauges software like an early beta version. I downloaded the "Wilhelmsk" app and it works perfectly with all nmea 2000 data without making changes device instance. Problem solved, and I have got the best integration and app I have ever used! Recommended! Thank you so much for explaining this to me, it got me on the right track after many days of troubleshooting.
@jurjenhoekstra Hi Jurjen, thank you for your input, I am still unsure how the unique instance adds up to the upper and lower limits ie 6 + 2 = 50? The image below shows the Device Instance column added and showing 50 but the battery instances still at 0 and 1. The instance 50 does not register any data on my display.
Also, I have added an image for the tanks/pressure sensors, as you will see they are all Device Instance 0 but Tank Instance 0, 1, 2, 5 respectively.
@Greg Ireland, hi Greg. Let's take a step back to your original question as to better understand what your are trying to solve: why are you trying to change the data instance for the BMV712? What is the exact problem? Is one of the BMV's not showing up on VRM or are you getting no data? This 6 + 2 = 50 does not make any sense to me.
By the way the setup on your yacht is quite similar to mine: Quattro 24-8000, Venus GX, Simrads and some Maretron stuff. Separate answer on the tank issue.
@jurjenhoekstra Good idea Jurjen, my vessel has 4 batteries, one for each engine, house bank and a back up navigation battery. I have previously been monitoring them via a Blue Power Panel and 4 shunts, however with the install of a Venux GX I was keen to get the battery data onto my Maretron N2K system.
I installed a 712 and connected my House Bank via a shunt and the Port Start Batt to the 2nd input to test, waited patiently for 12 months for the Venus Firmware to work and successfully displayed both batteries on N2K View. N2K View is configured to display battery instances 0 and 1.
Having had success, I installed a second 712 to monitor the Navigation Bank via a shunt and the Starboard Start battery on the 2nd input. But both are reporting on the same Device Instance, I would expect that I should be able to change it to Device Instance 1 (as it is the 2nd 712 on the system) and be able to change battery instance to 2 and 3 thus allowing me to separate them on N2K View.
As for the Tanks all report perfectly on N2K view, but it would be great to separate them on VRM for remote monitoring capability as I don’t use Maretron as it is silly expensive.
Thanks for your help, I really appreciate it - if you are interested you can see a bit more about my vessel at https://www.facebook.com/TSMVSeachange/
@Greg Ireland, hi Greg. Looked at your facebook page, great adventures. In case your are interested, I keep a weblog of the build of my yacht: Xanthiona. It has a lot of technical stuff, not so many adventures yet.
I did a search on the Victron Community on 'multiple bmv' and found there are some issues when trying to connect 2 BMVs to a Victron system. I believe it contributes to your issue of trying to get the information of both BMVs on the N2K View. Take a look at some of those issues, it might help or point you to the right direction.
To me it also would seem most logical to change the device instance and you would expect once that is done, that N2KView would be able to handle that. You could try changing the system instance, what we discussed yesterday.
On the other hand, it is the Venus GX who has to put the information from both BMVs onto the N2K network and as long that is done the same way for both BMVs without distinction between the 2, N2K will see them as one.
I think you might need some assistance here from a Victron staff member.
@mvader (Victron Energy), hi Matthijs, can you assist in this issue?
Hi @jurjenhoekstra, @Greg Ireland and @jonnys, thank you for all your questions and input.
@Jeroen and myself have been on the phone the last couple of hours spelling out all the nitty gritty details regarding the NMEA2000-out function in the GX Devices. As well as writing down in as clear and complete a manner as possible all there is to know about instances.
The result is here:
https://www.victronenergy.com/live/ccgx:start#marine_mfd_integration_by_nmea_2000
Can I ask you to close read & review? I hope it helps to solve your issue. If you have any comments, please comment to this answer. Thank you! Matthijs
ps: please look into using the Comment feature, rather than adding new answers when replying to someone else. It makes it really hard to read & catch up ;o).
Hi Matthijs @mvader (Victron Energy)
I have communicated with Maretron and they advise that the relevant data to them is the PGN and the Data Instance thus excluding the Device Instance as an identifying parameter. I can only assume that this a choice made by each manufacturer and therefore makes it difficult to mix the products. If, for example, Victron allowed the modification of the data instance so as to be compatible with Maretron then it would not work on the Victron platform, however, if Maretron recognized the Device Instance it would increase its flexibility and perhaps fit a broader market (but put at risk its own monitoring devices).
I have asked Maretron if they will consider this change, wait and see what their response is I guess.
Is it possible for Victron to allow modification of the Data Instance passing the responsibility to the user which way they program the devices?
Greg
Hi Greg,
The data instances are configurable. Device instances are too. Though I haven't used it myself, I've heard from my colleague that the Maretron software N2KView, tries to simplify things and doesn't show the Device instance as well as the Data instance individually. Instead, they introduced a new term, called Unique instance, with magic behind it.
I don't know how to use their software to change our data instances - and if thats possible. Please ask them.
On our products, the data instances are configurable using the NMEA2000 Complex write commands as per NMEA2000 specification. But you need tooling to send such commands.
I recommend to ask Maretron on how to best change that instance.
Best regards, Matthijs
Ps. I changed your answer to a comment, to keep it in a thread. Please reply by comment also in this thread, thanks!
Ps2. I've updated our documentation to confirm that indeed data instances are configurable.
I have several devices in nk2 networks that send battery data such as Multiplus, MPPT, rec-bms and smart shunt all connected to Cerbo gx- Without modifications, only two batteries are displayed on Raymarine instruments. (I have 3 battery banks) Changing the device instance as described in the Victron GX manual chapter 11.5.4 does not change anything on my Raymarine instruments. Using a programmable interface, we tried to change the device instance, the same result. When we change the data instance, batteries are presented correctly.
The question is why device instance is made available in the menu on Venus os and manual describes change of device instance. Are there other manufacturers this works on?
I run venus large image 2.70-3 on cerbo gx.
Had been very grateful for information that can confirm or deny my findings.
Hi, you are right. Raymarine requires changing the Data instances.
See chapter 11.1, and then find the document specific for Raymarine; and then go to the last chapter of the Raymarine document.
Other brands do work by only changing the Device instance.
Hi! I still can‘t figure out how to change the switch bank instance for the 702 or Multuplus.
Both units set switched on default switch bank 0. I want to uses one of the devices switch bank 1, as there is an overlap in switches 5-7.
This is also interesting when running two 702.
I am driving alarms from the switch bank with the AlarmButton for Yacht Devices.
Thanks for input.
Hi .. Good to find this thread.. after reading, I could successfully change the data instances of my smartsolar mppt (via dbus-spy in shell). By the way, not only raymarine had those issues.. also I use NMEAremote app together with SignalK - here I had the same issues with flipping values.
I posted my thread here: https://community.victronenergy.com/questions/232392/nmea-2000-mppt-and-bmv-show-battery-0-and-1.html?childToView=232555#answer-232555
but it is solved in meantime thanks to this thread..
I just wonder about the possible problems with that on my CerboGX system (like mentioned in the manual) .. is this only for skylla devices? How can I check if I have some other problems here now?
Thanks, Tig
