Silence Victron MultiPlus-II 48V 5kVA Inverter

[@foxythedirtydog4494]

My solution was to blank off all the vents at the bottom left and divert the air evenly around the transformer. When the Multiplus is charging it gives out a lot of heat and air was recirculating through those vents back up the right hand side via the terminal box at the bottom. As the relays don't need cooling, they are not affected. The improvement is very noticeable as the front cover is way cooler. Thanks for the tips and now I will check my firmware.

[@Raphael_Hofmann]

Wow, sounds like something the manufacturer should think of too...

[@foxythedirtydog4494]

@@Raphael_Hofmann I agree, it's a simple and free solution that only takes a few minutes giving a dramatic improvement.

[@dougle03]

It's not just the transformer that needs cooling, the mosfets also need good cooling too...

[@foxythedirtydog4494]

@@dougle03 blanking off the left hand vents forces all the cooling air to be drawn over the electronics so they are cooled far better.

[@UKsystems]

You should never do this first of all any issue caused by overheating and definitely void your warranty here and the approval safety standards will not be met. Therefore if this unit burnt your house down you would likely be to blame

[@NaamNatuurlijkniet]

Hi, Good video. A less powerfull fan may prove a somewhat hotter inverter at some point and thus a shorter lifespan. Seeing the inside of the inverter this way I wonder if some other better cooling method may even be more effective. Victron never designed these devices for sleeping next to them. I have to say, the rattling sound made me thing I had a faulty fan. The firmware, foam and rubber plugs are a great solution. I guess I would try rubber rings on the fanscrews to the chassis also as there may be some contact noise there also. All in all, a lot of improvement is possible in terms of sound reduction. We have to keep fireresistance in mind I think. In an other Video someone placed 2 extra fans below the inverter as well. I guess the fan speed is temperature controlled, so having an overall airflow thru the unit may help. I am even playing with the idea of connecting them to the ventilation system of the house, so that air is always running thru the units. It will collect much more dust I assume. Anyway, good video.

[@Raphael_Hofmann]

Yes, you brought up some good points! I will see, if I can do some more testing and maby I find some time for a follow up video.

[@NaamNatuurlijkniet]

@@Raphael_Hofmann Would be nice 🤣

[@Raphael_Hofmann]

@@NaamNatuurlijkniet Just found a very detailed discussion in the Victron Community: community.victronenergy.com/questions/46137/victron-multiplus-ii-485000-noisy-fan-replacement.html

[@Kanuka-Forest]

Excellent video, well put together

[@Raphael_Hofmann]

Thank you! I am glad you liked it ☺

[@uhjyuff2095]

Great job with reducing fan noise.

[@Raphael_Hofmann]

Thanks! I appreciate the compliment. Do you also have a MultiPlus-II?

[@uhjyuff2095]

@@Raphael_Hofmann no, I had a loud fan in my e-bike charger that I swapped the fan and it's much quieter now.

[@Raphael_Hofmann]

@@uhjyuff2095I see...seems like a lot of manufacturers have loud fans in their products.

[@christiancavallin3143]

I have drilled slightly larger holes in the Chassis and added rubber cable gland to isolate the screws of the Fan from the Chassis.

[@Raphael_Hofmann]

I am sure it helps! Are you satisfied with the result?

[@christiancavallin3143]

@@Raphael_Hofmann Yes I am. Unfortunately there is not enough space in the housing to do more or thicker rubber.

[@dmytrodance]

Before buying Noctua you should've learned the lineup of coolers they have... Static Preasure parameter... yet it's mostly matters when blowing through a dence radiator Thanks for the video! Please, post updates if any

[@Raphael_Hofmann]

The Noctua has very similar specs on paper. It fits well and is a good replacement as far as I can tell.

[@NancyPouna]

Amazing Video Thank you so much for The detailed information ☺️🔥💫 I now feel like a Pro

[@Raphael_Hofmann]

Thank you! I am glad, it could help you 😊 If you have any questions, feel free to let me know.

[@joachim8409]

Gretat video. Thanks for the step by step guide.

[@Raphael_Hofmann]

Danke!😁

[@kajakfahrerr]

n1 Australia gift , thanks for the video

[@Raphael_Hofmann]

Thank you! I am glad it helped!

[@jl9678]

Very nice. Thanks for the testing

[@Raphael_Hofmann]

You are very welcome!

[@5885ronny]

Gave auch eine Victron Anlage mit einem Lifepo4 Speicher läuft super gutes Video 🤗👍🤗👍

[@Raphael_Hofmann]

Danke, freut mich!

[@5885ronny]

@@Raphael_Hofmann 👍🤗

[@offgridsimplicity]

Nice job, well done!

[@Raphael_Hofmann]

Thanks 😌

[@UKsystems]

Remember only do modifications that Victor approved so some people have suggested things in these comments which would avoid your warranty and potentially your home insurance. If it was to burn down due to a modification it is worth knowing that you should never aim to run at its maximum power anyway so, sustained use it designing system better but they should really be in a fire proof room designed a block block sound anyway

[@nigelcharles511]

Helpful video. However I concur with the comment about fitting any fan that is less powerful. As well as a Multiplus 48v/5000 I also have a Quattro 48v/10000 which work together for EV charging off-grid. Even in the UK the summer temperatures were warm enough for me to have to fit external high flow fans to both inverters to ensure adequate cooling.

[@Raphael_Hofmann]

I should check out the airflow of the two fans at 24V as well.

[@SURO90]

Did you messure the temperature or was that just your „personal feeling“?

[@nigelcharles511]

I used the graphs available through the Victron software to assess the problem. Before I fitted the 'bilge blower' type of fans the Multiplus 3000 kept cutting out whilst it was running continuously at 2250W even at +8degC. The Quattro normally coped because or was running at about 50% power. The Multiplus 3000 was checked under warranty but no faults could be identified. Contrary to specification Victron inverters struggle to give continuous rated output at the quoted +25degC. I upgraded to the Multiplus 5000 and with the bilge blowers using internally mounted sensors and the inverter relays, the software could be used to decide when to switch the fans on. I used 100mm circular ducting with a rectangular adapter under each inverter. No problems since even at +33degC OAT.

[@Raphael_Hofmann]

@@nigelcharles511Wow, you put a lot of work into that!

[@nigelcharles511]

@@Raphael_Hofmann Hours of charging at 7.2kw in summer does seem to challenge the Victron specs. To keep the MPPT controllers from capping performance I also fitted pairs of 90mm centrifugal computer fans under each MPPT. Otherwise they could get too hot to touch when PV output and OAT are high. They are noisy but as this is in a hangar I don't care too much about the noise.

[@tiredofeverythingnew]

Great video Danke

[@rudydepooter9513]

Thank you for your video. I discovered the noise of the Multiplus II. A bit of bad surprise... Do you think the 140mm Noctua could be install instead of the 120mm ?

[@Raphael_Hofmann]

It should fit, but you have to build your own frame. By the way, the Noctua fan is not actually that much weaker. So it almost matches the Victron Fan when maxed out...just at 12V it was a bit weaker. Most important is the foam between the fan and the case. Even the Jamicon fan is not too bad, if you insert some foam to detach it from the case.

[@UKsystems]

Definitely not your warranty will not be covered and this is quite important with such an expensive unit

[@NaamNatuurlijkniet]

What if…. We would replace the fan with a Phantek T30, which is about one of the best 12mm PC fans on the market when I should believe all reviews. The big question would be, if it beats the original fan in creating a similar airflow with less noise that the original Victron fan. It beats the Noctua in PC cooling conditions. When we assume Victron chose the stock fan for the right amount of airdisplacement in certain conditions the Noctua may not be the best replacement. Although it may suffice depending on the environment the multi is used in. Who would vote for a review like that ? And would it be worth a beer or a cup of coffee ?

[@Raphael_Hofmann]

I had a closer look at the datasheets and converted the units: Air Flow: Nocuta: 186.7 m³/h, Jamicon: 187.89 m³/h Static pressure: Nocuta: 7.63 mm H₂O, Jamicon: 8.13 mm H₂O So the difference at full speed is not that big... I will try to make a follow up video...

[@NaamNatuurlijkniet]

@@Raphael_Hofmann Hi, If those numbers are correct, the Noctua and Jamicon move more air then the Phantek T30: 120 x 120 x 30 mm 1200/2000/3000 (+/- 5%) RPM via three modes 39.1/67.0/101 CFM (66.4/114/172 m³/h) 11.1/27.3/39.7 dBA 1.27/3.30/7.11 mm H₂O 4-pin/PWM control 0.05/0.13/0.36 A peak Assuming you used the nfa12x25 I found this: Rotational speed (+/- 10%) 2000 RPM Rotational speed with L.N.A. (+/- 10%) 1700 RPM Min. rotational speed @ 20% PWM (+/-20%) 450 RPM Airflow 102,1 m³/h Airflow with L.N.A. 84,5 m³/h Acoustical noise 22,6 dB(A) Acoustical noise with L.N.A. 18,8 dB(A) Static pressure 2,34 mm H₂O Static pressure with L.N.A. 1,65 mm H₂O Not sure how performance differs in the Victron as in most PC applications there is a Radiator or grill in front of the fan. Inside the victron is has more room I guess. Looking forward to the follow up. Tnx. Mike

[@Raphael_Hofmann]

@@NaamNatuurlijkniet Thanks for all your input! Some people install additional external fans. That would also work to reduce the noise.

[@SURO90]

„It beats the Noctua in PC cooling conditions“ - in short: nope

[@legominimovieproductions]

So even with the retrofit kit it still is better to install a noctua fan?

[@Raphael_Hofmann]

If you need to silence the unit even more...that is the way. But you can try the retrofit kit first and see if it is already enough for your.

[@xxwookey]

What was the cost of these various adjustments? I am looking at a Multiplus II and it would ideally live close to the living room. Nightime charging noise could be an issue.

[@Raphael_Hofmann]

If you go for the noctua fan and also the EPDM Foam...it should be around 40€

[@UKsystems]

I sell these people. Would you like me to advise you on how to make this quiet out of the box? As I have some resources available and I can make them visible to you if you would like these are official ones from the manufacturer?

[@xxwookey]

@@UKsystems That would be great. Thanks. I am likely to be buying one this week. I have learned that there was a change in 2022 and models made since half-way through that year are much quieter (and there was a retrofit fan controller provided for earlier models).

[@dougle03]

I notice no filtering in there at all... Gonna get really dusty over time that can trap moisture and cause corrosion! Shame on Victron for not adding some filtration and conformal coating to the more sensitive electronics in there.....

[@Raphael_Hofmann]

I have 3 of them in service in my basement for 5 years now...they are working hard every day and they never clocked yet. I will have a closer look at the corrotion resistance and conformal coating next time, opening one up.

[@tiloalo]

Mostly filter kills units as they get clogged and the unit then overheats...

[@Raphael_Hofmann]

@@tiloalo I agree, Victron does a good job in this regard.

[@UKsystems]

These must not just be any environment. Remember these products have an ingress protection rating the environment they are in must be suitable for this

[@legominimovieproductions]

I think I got a problem, I am using 50mm2 lugs which do not fit through the cable holes in the multi XD this is going to be fun when I remove the fan

[@Raphael_Hofmann]

I wonder which type of lug you use, that does not fit 😅

[@legominimovieproductions]

@@Raphael_Hofmann okay well they fit through the holes, but not through the cable gland I put in XD

[@Raphael_Hofmann]

@@legominimovieproductions Yea...I know the problem...In stationary systems without vibration, I do not use those cable glands at att on the 50mm² or 70mm² DC cables.

[@honumoorea873]

My 5kVA do not make noise.... it certainly an improved one.

[@UKsystems]

Potentially you are not using it at maximum power and you haven’t tuned a microphone to specifically pick it up when making an example

[@davebruessow6842]

I would be more concerned about the EMI/EMF from these units, if you spend a lot of time in close proximity to these units. Thank you for sharing...

[@Raphael_Hofmann]

I did some measurements and in 4-5 m distance, you can not measure any EMF anymore.

[@davebruessow6842]

@@Raphael_Hofmann so then, if you are within 4 to 5 meters, you will be in range of/exposed to EMF/EMI emissions. Sounds about right/typical, and they can be quite annoying/uncomfortable (especially the high pitch from frequency inverters). These things absolutely need to be isolated from the living space or anywhere you spend a lot of time (where you could be exposed)...

[@UKsystems]

That is not harmful the device you are watching this on unlikely admits more any type of product like this has to be tested to ensure it’s below reasonable levels

[@davebruessow6842]

@@UKsystems sure, radiation is good for you. Cheers, mate...

[@UKsystems]

@ it’s electromagnetic fields not radiation. It is safe. The wire in your walls put off more than these units so if you’re actually concerned you wouldn’t be using electricity or watching this video.

[@janh.1200]

I guess, your Fronius is more noisy as the Victron

[@Raphael_Hofmann]

Well, I think the stock MultiPlus-II is a bit louder than the fronius.

[@MrButuz]

Be very careful fitting a weaker fan - taking 25% off the fan power could cause premature faliure and I can't imagine you'll be getting a warranty replacement. People are always fitting noctua fans to things and going oooh its so quiet - yes it is as you'r running your unit 30% hotter than it was.... :/

[@Raphael_Hofmann]

The MultiPlus-II does not only regulate the fan speed on a fixed Load-Fanspeed-curve. It is also regulated on temperature. And if the internal temperature gets too hot, it is derating its output power to protect itself. From my experiance, running this configuration in Germany, it never gets too hot, even with the Noctua Fan installed. Especially in a ESS-System, when the output power is limited to 4.3kW.

[@Raphael_Hofmann]

For a hot climate, you can just stick to foam and rubber wallplugs...

[@Raphael_Hofmann]

I agree in terms of Warranty...you probably void your warranty.

[@SURO90]

In most cases the Noctua fans are quieter AND push more air than the cheap fans … you could use the industrial fans if you live in hot climate … so no idea where you are coming from when talking about „people always …“

[@UKsystems]

@@SURO90 however most cases is not good enough Victron very frequently change slightly details potentially what speed they use