question

@jeanmarie

I have quite a few cerbos in the field with no issues so far. And out of all the installers I know, no failures so far. Don't forget when people dont have a probemm they dont come onto the forum to say that, so here, all you will read are problems.

Each component of the system will work without the cerbo if they were never plugged into the cerbo.

Them mppt will probably stop charging if your system is bms controlled, it is easy to fix that reset to stand alone, it will use its own charge algorithm and work.

The multiplus is possibly also waiting for a bms control. If not then it is not programmed correctly. That should run without a GX at all if programmed correctly. I have seen many Victron inverters in the field also with no GX of any kind attached.

The cerbo is the key to bringing the whole system together and if ESS is installed (it is definitely a requirement) the co ordinator of all things. And the reporting monitoring centre.

But can the components work without one? Yes.

Hi @Alexandra and thank you for participating

I know that most of 90% of people with issues are participating to forums when almost less than 10% of those without issues are, I'm quite familiar to forums.

I must then have been really unlucky to have one multiplus out of the box with a failure (and for which my installer was forced to sent it back for repair instead of getting a new) and one CerboGx that crashed 2 weeks after being powered up. I was expecting a bit more reliability regarding the price paid for the brand, ok, definitively I must be just unlucky, for sure.

Regarding the capacity to change behaviour of a multiplus or a RS450 to work without a cerbo after being programmed to work with : do you have any references of documentation explaining what to do and how to do it (I guess a MK3-USB is then mandatory). Because switching it off and then on doesn't let it go back to charging

The same for the multiplus if it was programmed to use communicating BMS/ESS and you loose it, then it means you must reprogram it through MK3-USB, but you also need to implement a wired solution ("allow to charge" and "allow to discharge"), right?

You certainly experienced something unusual. We have not had a product faliure yet on our installs.

What I have seen is the warranty support is next level and product lifespan as well.

Everything you need to know is available online, YouTube has a few short videos on the victron channel. All manuals are available and even walk through video as well as free online training (yes even for end users)

Victron Connect with your mk3. You should be set. It even makes firmware updates so easy.

All products have manuals, these include how to install. Multiplus 2 here and cerbo here, at the bottom of the page linked.

And of course there is this forum.

What batteries do you have? Are they from the compatible list? If they are then there are good instructions for each if them. If not, don't stress there are plenty of people that have systems with out the officially supported ones.

As said, I voluntarily choose Victron for it's experience in the storage/ islanding and reliability, just I'm used to work with DCS system like PCS7 and Teleperm M, also high value system from a well known german provider and I never ever experienced such issues with 2 damaged unit in such a short period of time, but never the less we will say it will give me the opportunity to learn how after sale service works (those from my provider and the Victron local services) : For now it is not as fast as expected as my faulty multiplus was sent for repair already 10 days ago.

My batery is not in the compatibility list (Seplos BMS) but was well recognized and working in conjunction with a multiplus/rs450/cerboGX and Fronius inverter like a charm for those 10 days up to the failure of my CerboGX.

For the manual and others, yes I already read quite a lot about, but as there are so many functions and possibilities, a great part is based upon knowledge and experience I do not have. For RS450, I saw from victron connect that I have to reset default parameters or connect through VE.Configure to deselect the use of a BMS : ok, this is manageable "in case of failure".

For the multiplus it is another story : first it is an "old" multiplus-I without bluetooth (as my main unit is in victron's office), but could you advise me what to do to get inverter back at work in case of the lost of the BMS function?

Should the assistant VE.Bus BMS be forced installed together to ESS and both wire (like those suggested Aux i/O / Temp Sense) be placed to allow the use of the inverter in case of the lost of the communication? Or is there some other parameters to define to be able to have a more reliable installation capable to resist to the failure of this small blue box named CerboGX?

Many thanks for your help.

@jeanmarie

For the RS 450/100 it is easy. See the manual here when you see the error 67.

The multiplus you have to remove any programming related to BMS control with the mk3. And make sure the charge voltages are correct to charge the system as a 'dumb' (meaning no communication) battery. The ve bus bms assistant is only for victron batteries not other bms systems by the way it is the two signal bms assistant for third party bms control.

Thank you @Alexandra

Many thanks for the link to online training, didn't knew it, it is really helpful.

For the RS450, as said above, the message given by the victron.connect/bluetooth is crystal clear. Just without a MK3-USB interface you have no other choice than to reset to default settings and reconfigure proper float/bulk voltages. Not as smart as the product name is pretending but this is only in case of failure.

For the multiplus this is fuzzier, the only certainty is that a MK3-USB interface is a must for anyone who want to depend a bit less from the availability and opening hours of their installer.

It is right that a multiplus is inverting from bateries without the cerboGX. Mine unfortunately is not working if the grid is present (only passthrough if the grid is on) and inverting is playing with frequencies jumping from 50 to 60Hz very fast : meaning not usable as it is. As I don't have any MK3 device I cannot look inside and will have to wait for my installer to see where the problem is.