Funny you say that… All cheaper Chinese inverters has this HV DC bus soft start converter… 
Because you have a 450/200. Rated to do 200A continuously.
A 160A pulse is well within nominal power rating.
A separate 2W DC/DC converter would add cost and complexity.
Ok so you are saying that a 160amp current pulse is ok because the MPPT is rated to deliver 200Amps. What I think you are actually telling me is that there is no upper limit to the current pulses other than the source and MPPT internal impedances. That not having a limit to the current pulse is a cost cutting exercise and not based on proper engineering practice. That a paper specification for standby power of the MPPT for advertising is more important than overall system performance as losses outside the MPPT are ignored.
In this case I think the standby power specification of 15mA is misleading and it should be specified correctly.
I also expect better engineering from Victron so am very disappointed with the MPPT.
I will be removing the MPPT RS and installing a well engineered product in its place which I have already chosen.
What I think you are actually telling me is that there is no upper limit to the current pulses other than the source and MPPT internal impedances. That not having a limit to the current pulse is a cost cutting exercise and not based on proper engineering practice.
That is not what I wrote. The DC/DC converter is regulating the current to a safe level, of course.
Your comments have been forwarded to the engineering team and may be taken into account for future updates, but I cannot guarantee it.
That’s your decision and we’re sorry that you feel this way.
if the MPPT has a current limit on the pulse could you let me know what it is as it seems others have lower current pulses than what I am recording. Am I at the current limit with 160Amps or is my current limited by the total impedance. Is it a designed in limit or are smart FETs used and their internal protection relied on to stop damage due to over current. In any case I would call into question the quality of the engineering in this product.
If this is on a 200A mppt (which is more than capable of 5his) then the wiring fusing etc in the installation should be rated for at least that. These spikes would only be a problem in wiring and fuses batteries in a installation that is under spec.
And 160A peak is not the same as average; worked out to 1W; the 15mA still is correct as you work it out.
Even at 160A, the time-averaged RMS current contribution from these pulses is tiny.
0.02s pulse approx every 114s = duty cycle of 0.018%
From an engineering standpoint smaller peaks more often would actually make it more inefficient as there will be more switching losses.
Measured consumption from the battery is 1.6W so more like 30ma. This is not my issue as 30 or 15ma is irrelevant in the overall schemes of things.
The bigger issues are with short current spikes that are not contained within the MPPT are making it to the batteries where they do not play well with current shunts and other equipment etc.
So from a system point of view lower current pulses are better.
You also have the issue of the current spikes being randomly additive if using more than one MPPT.
The large current pulses for standby operation are poor engineering
I have an 800watt average night load on my system the standby current of the MPPT is irrelevant.
For some people it matters and I think you did bring it up as a concern for averge power consumption figures.
Again adding more mppts would mean a person has a system load that needs that kind of power which would then alter the base build.
Shunts should have some kind of averaging on them. At least the Victron ones do and so do others i have used. And it should not damage them as they would be rated for the current? Tbis is a oulse out not in so slightly different to needing to be absorbed.
All i can think for other things is maybe a voltage sag? I have never seen or had a system experience it enough to affect other things.
I’m always interested in learning things outside of the scope of my experience so what things are you referring to and what is the effect?
I measured the MPPT RS 450/200 current pulses at the battery bank in a working system. I should have realised that this is not correct and that there are 3 x 240v Selectronic inverters also attached at the time of measurement and these inverters have large directly connected capacitors across the batteries. I fully expect the actual current pulses from the Victron MPPT to be much larger and shorter duration than what I have mentioned here.
I will use an isolated scope across the shunt to the MPPT tomorrow and see what we really have going on.
That would cause an interesting reaction for sure. Am keen to hear more.
It would certainly tell if it is coming out of the battery bank. But the mppt side will be different to isolate.
Indeed, with an additional 2W DC/DC converter will be saved only about 0.5W of energy…
Energy is VxIxt and it’s about 48x150x0.02 = 144J, so about 1.4W, with 70% efficiency let’s say about 2.1W.
The 150 A current sounds scary, but because it lasts only 20 ms every 100 s, the RMS contribution is tiny, about 2A.
A tiny flyback converter might achieve 80% efficiency at 2W, plus controller quiescent current, plus transformer core losses running continuously, so input power might be: 1.44/0.8 = 1.8 W
You would save perhaps 0.3 W compared with the pulsed method.
Given pulse figures (144 J every 100 s), I would expect the dedicated 48→450 V / 2W converter to improve standby consumption by less than 1W, and possibly only 0.2-0.5 W, unless the main boost stage has unusually high overhead when awakened.
Still, from another perspective, such small 2W DC/DC converter will cost only about 10 euros, usual parts considered…
I’m currently working on an accurate capture of the current pulse at the current shunt that is dedicated to the MPPT.
One thing I have noticed is that the current pulse is very audible even with a bit of background traffic noise you can still easily hear the current pulse.
As an individual, yes.
Putting that into production as a company requires time, re tooling, re design and whole load of other revisions. So not 10$ or €
R&D is done, for sure, in house, up until the new Gerber files. So the work is paid/included in the same salary for the R&D employees.
Then, on the next batch, for the PCB manufacturer is the same thing/price, as long as the PCB surface is the same and for sure will.
The only added cost will be with the added components, which will be recovered on the final price.
I know as I’ve designed hardware and software for casino/gambling equipment for a few decades.
And there, boy…, even a small mistake could translate to millions, sometimes the entire company worth.
So imagine the pressure for all to be perfect.
But then again, I understand your point and already acknowledge that it makes little sense with a permanent DC/DC converter.
I have now made current pulse measurements at the MPPT rather than the battery bank. The new measurements include current supplied to the MPPT RS from capacitors in the Mains inverters.
This adds about 25Amp to the total taking it to over 180Amps (delta Y)
I haven’t traced the source of the audible sound of the pulse but given I will be removing the MPPT RS it’s not worth any more effort. The following positive 60amp spike always occurs but again can not be bothered chasing it up.
This is not a design for Victron to be proud of given the large current pulses are external to the MPPT RS ensuring it does not play well with other components in a system.
Yes not cheap after the product has been signed off to make this type of change. Add retesting for environment, thermal cycling/life testing, EMC, vibration (I doubt they do this one) and more.
The MPPT RS is not going to do Victron reputation any good. Like they say it takes a lot of great products to earn a good reputation and only one bad one to wreck it.
It’s the big HF transformer inside.
Below you can see it and in the second picture the 48V DC capacitors and FETs on top of which the transformer is placed.
You can also see on the right the bank of the HV capacitors.
They store about 300J of energy, about half of a 9x19mm Parabellum round.
The first down spike is the start of the converter and the second one, upwards, is the stop, after 225ms, it seems.
The loss is fully recovered after 100ms.
Surprising comparison of energy 
Sorry, power of habit… Licensed firearms instructor as a hobby…
So in contrary, in your training you warn people that a 9x19mm Parabellum hurts as much as touching two RS450 HV capacitor banks?