Correct and the fact that the firmware is not in beta yet.
This whole thing is very confusing to me.
The Multi RS is also rated for 50Amps like the 5000 va Multi Plus 11. How does the Multiplus deal with relays that does not open at the same time.
What confuses me even more is why this is an issue. When do we expect the Relay to open, or when will is normally open in sunny SA. 98% plus of the times it will be when load shedding starts. Sometimes when the voltage goes to high or low. In effect for 98% of the situations, I cant help to wonder where the current will come from if the grid has failed. I mean we are talking about the Grid relay here, we are worried if it can handle the current flow. What current flow are we expecting when the grid fails? And again, the question pops up, how does the multiplus 11 deal with this situation.
Now lets look as real world example.(the way I see it might be totally wrong)
I need 7 kw peak inverter power for my home, 1 RS wont do it, right, although its Passthrough rating is 50 amps I would only need appr 28A. SO when I design my system I don’t take the Passthrough rating into consideration, I only design for my loads. In this case I would need 2 inverters in parallel. What happens when I have 2 inverters in parallel. The load gets divided 3.5kw on each. Furthermore I no to limit the the current from the grid to ensure that I don’t exceed the 63 amp rating of the supply breaker. (Hold on I am going somewhere with this) . Now I add a 24 000 BTU aircon to the mix and install a heat pump for my swimming pool and all of a sudden my peak load goes to 14kw and i add a 3rd machine. the load again is split over three units and the demand from the grid divided into tree. A year later I build a flat for the mother in law and add my 4th inverter to the mix after I ask the council to up my input breaker to 80 amps. Theoretically I can now supply a load of 96 A, but the input current limit is set to 20 amps per inverter. the max load I can draw from this inverter is 24amps i did not overload the system.
And here is where I am going with this story. The more units in parallel, the less the current that will go through that relay at any given time. Even when the unit disconnects due to high voltage. The ac loads and requirements at that time is only related to the load on that specific inverter. If unit one opens first, his AC load is not passed to the relays of the other three units. His load gets passed to the battery/panels. If unit 1 to 3 open at the same time and unit fours relay is still closed the current through that relay will equal to the load of that unit and not the combined loads of the system.
@plonkster , please show me where my thinking is wrong, but imo the more units in parallel, the lower the loads per unit and the lower the demand from the grid, the less the stress on that relay and the lower the risk.
After a discussion with Izak now, its clear that once you reach minimum SOC the risk of the relay taking more current in the event that they don’t open at the same time increases, To what extend we are not sure.
The statement from Izak has a few of my clients considering returning their inverters. We installed single units with the plans to add more in the future and those customers now want answers from me. We made decisions based on previous datasheets, that has been removed/changed after we installed the units. This leaves us in a difficult position as the customers now lose trust in our prefered brand.
We are in any case to small a part of their market to really be heard if we voice our concerns, yet they threaten to remove us from authorised status if we touch any other brand. We promote their product only get thrown under the bus like this.
This is truly not the image this brand needs, its hard enough to stay afloat in this market while competing with other cheaper brands, we don’t need these extra issues to deal with.
What is the purpose of this? Why would they have a policy like this, it really does not instill trust?
An approved installer, who got the job on account of getting this recommendation on the website of a high quality manufacturer, shows up and installs the cheaper product of a competitor. It creates a conflict of interest when you recommend someone who installs products other than your own. It is that simple really.
There are many installers who install competing products, and that is fine. Then you do your own advertising.
From Victron’s point of view. Izak, it is time Victron starts listening to the problems we as installers face trying to sell their product in the South African market. They brought this new competitive product into the market, and now tell us we have a problem. No that’s a lie, they told us nothing, you did, because you feel its the right thing to do.
We are busting our balls, trying to keep your brand on top, but some customers bluntly refuse and insist on another brand. The market have been very slow for the last 6 months, many of the major Victron installer dont have work, some only doing their first install in March this year, living of their savings and investments. Many many installers closed their doors in the last couple of months.
If I have to choose between having an Approved status and feeding my family, I will always chose the latter.
You can find an approved Sunsync installer on their site, with recommendations, does sunsynk have the same policy? No, Never.
Out of hundreds of installs we have done, only two came from the site.
You are not only a forum member, you are a friend, I will rather leave it at this.
I hear you, but I’m R & D. Not my place. This needs to go via sales structures.
For what it is worth, the classic Multi is not immune to this problem. Those relays work hard in a parallel setup. Something better will be done for the Multi RS. I do believe transparency is important.
Awesome, so the risk is the same as with the Multi 11, probably using the same relay. Now i can relax, as I have experienced no such issue with any of my Multiple Multi installations and I know of nobody that did.
You know this is not possible as the man enforcing this is the one that will receive my mail, and he already indicated that he would not listen to reason.
Load shedding – which is no longer just a South African thing – is challenging some design decisions that goes into the hardware. We have to remember that engineers make compromises, and some of those decisions were made a decade in the past. They have a specific use in mind. A capacitor that lasts forever at room temperature may last only a thousand hours at 105°C, and it is right there in the spec sheet 
Lets call it what it is. This risk have been present even in the Multiplus11, we never knew about it so nobody worried. The Multiplus 11 proved to be reliable in multiple unit configurations even during the load shedding periods. This puts my mind at ease.
I appreciate if they now want to lower this risk by improving the situation even if it is by adding a separate device to ensure simultaneous disconnection from the grid.
It is reassuring that the problem is not a new one as everybody expected and I am glad that its not only Victron that has this issue and so far although the risk exist on paper, there is no cases that I know of where it actually happened.
I will sleep sound tonight knowing this, because i know what the Multiplus 2 is capable of and also now know to expect the same from the RS.
All this worry for nothing.
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As @plonkster mentioned, “there is already a second hardware revision that changes how the bonding relay works… makes it the same as in the later Classic Multis”.
As we know with hardware revisions comes incompatibility.
With no paralleling as of yet and a new hardware revision already, what are the chances of it working with our currents RS’s ?
@plonkster do we know when the new hardware revision was released? I am trying to see where I installed old ones and where I installed new ones. For my last one I installed inverters I bought in Feb.
The new revision uses a different method to test the bonding relay. Has nothing to do with the transfer switch or the future ability to parallel.
I think the dual tracker machines all have the new arrangement, though not sure.
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Question. Would that not automatically come up under Firmware updates?
Asking because if you ask that question, what is the curve ball I’m missing?
Hi there
We have a month and a few days before the end of Q3 2024.
Has there been any update on the NRS certificates?
It’s been a while since Q3 2023, we are now Q4 2024. I am not even seeing anything in the beta program. It feels like the wanting to make this promise good has died. Is Victron is hoping no one mentions it again?
Also no NRS certificate for the Multi RS to date, according to the letter from Reinout Vader that was expected Q3 2024.
Grid code support is in the latest beta firmware and release of that firmware has been imminent for some time now. We’re talking weeks, not months.
However… it won’t have NRS097 yet. While this is perhaps a bit of an abrupt answer, the answer might be to replace those units with Multiplus 5KVA units, and lay it to rest.
Would love to do that… Need to do that actually.
But that is not a cheap exercise, its the Multiplus 5KVA replacements, the Smartsolar MPPTS RS, and the labor of changing the whole lot.
I mean, I feel a bit bad about this. There has been somewhat of a miscommunication, I think, but some of it is also just the fact that humans sometimes overestimate, or things happen that were not envisioned. Keep in mind that the entire team making this thing is less than ten people. That is good: Most successful projects are not made by super large groups of people. But unfortunately it sometimes creates delays.
That is why we really should not be promising things. They happen when they are ready. Otherwise you end up with something half-baked.
The grid code support is now – with that same proviso mentioned earlier – expected before the end of the year. But by that I mean simply that the basic ability to support grid codes will be there. And VDE support almost always comes first, because once you pass that, the rest are almost formalities.
I’m sorry that I (still!) don’t have better news.