I am running three RS/48/6000/100 inverters as a three phase system in an installation on a Cerbo-GX together with another RS/48/6000/100 single phase, a VM-3P75CT Gridmeter and a Smart Solar MPPT VE.can 150/100. In adition there is a 40 kWh Voltsmile Battery system connected. Sometimes I am getting the error code Error Code: #76 - Network misconfigured on the Units that are configured as three phase system. The system may run 10-15 days without a problem, but during these short errors that last between 1 and 8 seconds the inverter relays klick and seem to shut down and restart the 3 Phase system. All other components in the system do not show error #76. The first component in the CanBus string is the Grid Meter. The three phase units are on the other End and the last one has the termination resistor. The cables are so far ok. How can I get the three pase system more reliable?
Take this one off the GX.
Or remove the battery connection/reference and configure and run it as a pv inverter if you need the solar.
The Problem existed already before the single phase unit was installed. So it cannot be the problem. Besides that we need the data in our installation.
It remains as data when it is a pv inverter. The set up is not supported sharing the GX for two systems.
I will ignore for now that then.
Are all the components on the latest firmware or were they installed and updated with the latest firmware?
Has prevent can network island been enabled?
Thank you for your understanding.
All connected componnents were frequently updated several times after they were installed. The GX runs on firmware 3.67 latest would be 3.71
On all 4 RS inverters prevent can network island has been enabled.
Are they running in the same or near conduit with ac or dc cabling sometimes is random interference or something like that.
Yes, they are relatively close together, but I have not much choice to change that.
Is continue with missing phase also selected (if you don’t have three phase devices?)
Sometimes reliable and pretty can’t be done at the same time.
Since it is an intermittent fault finding it will have to be a process of elimination. One thing to eliminate is interferance.
The three phase system used the system Instance 0. I now set those three units to instance 1. That reconfigured the VRM Instancees of those units too. I then received Email messages which said that the status of the units had been changed from misconfigured to normal. Besides that, the Remote-Console now shows two systems. The three phase system is one system and the sigle phase system is shown seperate. It is still on system instance 0. I now need to wait a few days and see if the #76 error shows up again. If not I will set the post to solved.
Still might get some weirdness. A GX is really only designed to control one system. You have two connected.
Is the grid meter supposed to control both systems?
It is an Island system with no connection to the external grid. Both so called system instances have an independant output to different systems. So the grid meter is used for information purpose mostly and has some functions in our node red programming. As far as I understood an installation should not have more than one GX. As all units work on the same battery all units have to be controlled by the GX that has the battery connected. I see that Victron is adding features all the time. I think that the idea of a unit instance would be obsolete if a GX could only control one set of inverters. So maybe things have changed. We will see. Thank you for your input.
Indeed sounds like a software bug or configuration error. “Take this unit of the cerbogx” comment should be deleted. We have system instances on RS series exactly meant to have multiple RS systems on a single GX. Besides that the three running inverters as threephase are probably configured with minimum 0 or 1 inverters per phase. So it should completely ignore the second inverter on phase 1….with a different system ID. Now if that extra inverter also has system ID 0 than there is a conflict whenever AC-in voltage is available. Because multiRS firmware can only handle 1 inverter per phase when used with Ac-in function.
Sorry that answer is not really valid anymore there are hundreds of systems out in the wild with multiple systems vebus or RS or a combination of both connected to a single gx device. It depends on the functionality that you want if this works perfectly or not.
ESS and DESS systems need single system on GX but simple backup or island systems can easily share a GX
There are specific supported configurations for this which are documented along with the related limitations.
If you ignore limitations and do as feel you will have issues as there are architectural challenges, and the configuration will be unsupported.
Please don’t treat me like “as you feel and ignore “ you will run into problems…
There are many cases where you really need 1 GX, 1 managed battery and for example three RS systems.
Situation example TV/Radio studio with guesthouse in same building.
Floor 1 TV studio. Clean power RS system ID1
Floor 2 practice studios clean power RS system ID2
Guesthouse RS system with connection to grid on ID3
All system share the same battery bank and in case of solar deficiency the Guesthouse system can help charge from the grid.
From VRM you see 1 battery, 1 amount of solar and AC-out Watts are also nicely added up together. Very convenient monitoring
Except we have never supported multiple independent systems off a single battery let alone sharing a gx. It may well work but it is unsupported and what works today may not work tomorrow when software is updated.
How you configure your systems is your business. Its up to you to accept the risks and consequences if it has issues.
As a victron site we encourage best practice so this is for others who come across a topic and assume this is an official config and then come report issues here when it goes wrong.
I can add to this discussion perhaps I’m having exactly the same issue with my 3x Multi RS since a few days.
I don’t have anything special other than the 3x MultiRS with a Cerbo and victron’s VM 3phase grid meter. Relays click and disconnect for a few seconds and throws a #76 error occasionally.
The Multi RS settings –> Grid –> NS protection log also shows “Multi-Phase Issue”. At least the timing of this last error corresponds to the install of GX SW 3.71, might try rolling back if it’s persistent.
You might have not realized that I mentioned earlier that the #76 error was there before I added the fourth RS unit. So you might be right with your comment. However I do not belive that two systems with individual outputs are not supported today. There is the feature Systeminstance. If you open it, it reads: Units with the same Systeminstance work together an can be operated in parallel or three phase mode. Use this mechanism to use several Systems on the same Can-Bus that are not connected on the AC-side.
No, it is not switched on in the three phase setup. I don’t like the idea to run the system with a missing phase. Why did you ask?
The system allows many different configurations, plenty of those will not be supported - like cascaded inverters for example.
If the architecture is not documented in the GX connectivity manual (or the RS manual), then it is not supported. Doesn’t mean you can’t do it though.
RS is CAN based not VEBUS which has its own limitations.
Nowhere is it stated that multiple independent systems is supported, that you can connect them via CAN and the GX sees them is not the issue, it is that this is not a tested and qualified config so problems may be experienced and more commonly after updating.
Like any issue, you would need to rollback to a stable previous version (3.67 in this case as 3.70 and 3.71 are a similar branch) and then demonstrate it occurs in a supported configuration.