Cooling our Victron equipment - your suggestions, my solution

We are having a look at the electrical cabinet enclosure and what the best way is to cool down the equipment inside. You made some good suggestions her on the channel which got me thinking of the best way possible to install an effective cooling system.
Here is my idea. Well, it's to late now as I have already cut into the door. Will it work though?
Linus Tech Tips Airflow Experiment (more about dust but also explains the air pressure inside an enclosure):
• 1 Year Airflow Experim...
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[@Sylvan_dB]

Don't expect good results trying to series electronically commutated motors for a higher voltage. Even regular brushed motors don't do well in that situation, but at least there you are less likely to exceed the voltage rating of electronic components. (Use an oscilloscope to see the voltage spikes across each motor.) You can get 48v rated fans but I think a 48v to 12v DC:DC converter is a better approach.

[@hansjrgenkristensen4034]

Wondering what kind of solution he comes up with, 12V PC-fans should have about 12V for safe operation. Dc 48V to DC12V can be done with optional converter. E.g. in the batterybox and cord from there. Convenient with thermostat connection in the inverter - if it can be done easily and it works. Fun to watch the videos - it is well thought and he comes up with good suggestions and changes - as well as has many following on KZbin.

[@andrewsweet43]

Be sure to add a small inline fuse to the fans if you want to run them directly from the battery pack! I wouldn't want to imagine what would happen if one of those fans sorted out with the full battery voltage on its back...!

[@OffGridGarageAustralia]

Yes, absolutely. Next video tomorrow ;)

[@budmartin3344]

BTW, your batteries is around 55VDC or more, so can your four 12VDC fans in series handle the over Voltage? Also if the fan circuits are not matched, some may have more or less than 12V Vdrops on the fan. What tool did you use to cut the panel? JigSaw?

[@OffGridGarageAustralia]

They can run on 24V for a shot moment, so yeah, no problem. Yes, just a jigsaw and metal blade. Wasn't too hard actually

[@ebenwaterman5858]

That's fine. You won't ever be able to measure any pressure differential. Heat out at the top, cool in the bottom. Perfect. On to the next thing. :) I wish the inverter had an output contact indicating approaching over temp. To control the fans.

[@OffGridGarageAustralia]

The inverter has exactly that.

[@ebenwaterman5858]

@@OffGridGarageAustralia Yay! I see from your other comments. What's your latitude? Are those trees gonna be a problem in the winter? :)

[@NaughtyGoatFarm]

Nice job Andy.

[@OffGridGarageAustralia]

Thanks 👍

[@PietjeNL]

Can the Victron inverter switch the fans, or are there no programmable ports?

[@OffGridGarageAustralia]

Yes, that's exactly what I will do. The inverter has a programmable relay for exactly this function.

[@DutchAussieProductions]

Nice job. All that ventilation should make your equipment last a lot longer. Those inverters generate a fair bit of heat on high loads.

[@OffGridGarageAustralia]

You are right!

[@scantrain5007]

Hi Andy, it's now too late... Your Idea to put the Air-Inlet at the lower part of the cabinet's door is ok. But I would never put the active fans in the door! Because of the wiring for power supply. I made some bad expieriences about this. So Fans alawys in stationary parts - here on the sides. And... never take fans which need to connect in series. Better take other ones which runs in parallel mode: If one breakes the other ones still running. However: Happy easter + stay healthy!

[@OffGridGarageAustralia]

You haven't seen the next video yet?

[@vaneay]

will you make a temperature controled start for the fans ? They would be annoying hearing them running all the time.

[@OffGridGarageAustralia]

The inverter has already a temp sensor and switches the fans on when needed. They are whisper quiet... you cannot hear the at all

[@Josemanc]

What no froggies?. Hope the cooling fans work mate. Love your energy btw

[@OffGridGarageAustralia]

It's getting colder outside now, so froggies will be sleeping now.

[@Josemanc]

@@OffGridGarageAustralia I love you take te time to reply to our comments

[@Josemanc]

You rock

[@6sensory]

Parallel fans (110v) for redundancy at the bottom, blowing IN. Holes at the sides and top and front. Allow heat to get out every where, with a gale of air in all directions. I had to do that with my concert sound system amps. Heat needs a way out - an EASY way out. Cheap house type air filter across the outside of the fans, so they suck through it. Make guides to hold air filter for easy replacement.

[@MrSummitville]

110 Volt fans? Nope....

[@GEORGE-jf2vz]

On our equipment at work we put in an air conditioner unit made for enclosures. Not super expensive.

[@janbroz4681]

I think it would be better to run them parallel and use buck converter to step down the voltage to 12V, series connected fans give you single point of failure, parallel are redundant, if one fan fails in series they all stop, in parallel, only one stops.

[@OffGridGarageAustralia]

On the other hand you're adding more complexity with a buck converter. And more heat.

[@ulven75]

What about to install a 48v temp sensor relay to start and stop the fans ?

[@OffGridGarageAustralia]

The inverter has already a temp sensor and switches the fans on when needed.

[@johnc5937]

If you fig’r out what you're doing you might like this job.

[@briansomers4753]

Two small compuer fans set up with temp controller

[@OffGridGarageAustralia]

We're going BIG, Brian 😉

[@briansomers4753]

@@OffGridGarageAustralia Andy checkout sonoff internet switch this is what i use to turn my fans on and off automaticly...cheap solution...get the one with the temp prob

[@briansomers4753]

@@OffGridGarageAustralia P.S. I stubbled across your channel and have been warching for a long time knoweven watched older stuff... very entertaining and fun to watch...I've even picked up some good info

[@MrSummitville]

@@briansomers4753 Why? The inverter already provides this control ...

[@man4evil]

LOL 😆😆😆 btw add temp sensor to only cool the case when needed to make it less noisy if it bothers you

[@OffGridGarageAustralia]

The inverter does this already.

[@shadowpotatoe9482]

That's the kind of mistake id do lol

[@lhffan]

More fans in = less dust

[@ebenwaterman5858]

Hope the truck brings more solar panels. The sun gets pretty low come June and July. I'm at 44 North lat. where are you.

[@Lawiah0]

i love how the Sun moves over the flat earth.

[@ebenwaterman5858]

@@Lawiah0 The sun gets low in winter on all Earth geometries. Up here it's kinda spherical. ;)

[@Lawiah0]

@@ebenwaterman5858 that's why the surface of water, no matter the shape or size of the container, is always flat.

[@mikenewman4078]

@@Lawiah0 April 1st was yesterday.

[@Lawiah0]

@@mikenewman4078 i see people acting the fool, daily.

[@bobham919]

you got plenty of volume with all the fans i run those kinda things at 6 volts per fan then they are very quite.

[@TheGalifrey]

There will be no imbalance as the fans will be no where near capacity of airflow. You would need to exceed the maximum airflow of the 3 holes with 4x 54cfm pc fans, night on impossible.

[@junkerzn7312]

Should be fine running the fans at 12V, they'll just run a bit slower. You went overkill on the number of fans (you really just need one intake and one exhaust fan), so it probably works out pretty well, and it will be quieter. -Matt

[@monsieurd.6890]

In fact I would just have removed the door lol !

[@OffGridGarageAustralia]

The purpose of the cabinet is to keep dust and insects out. An none existing for does not help 😉

[@monsieurd.6890]

@@OffGridGarageAustralia good answer I forgot it was in Australia lol.Not as much trouble for that in France so I will just put all my stuff in a massive closet with a big mesh (wire rack, I am not sure in English) at the bottom and at the top of the closet doors.

[@FatgirlMickey]

My only question is what makes u think i needed 4 fans.

[@OffGridGarageAustralia]

The answer is: each fan has 12V and I have a 48V battery

[@FatgirlMickey]

@@OffGridGarageAustralia i was wondering if 1 fan would coolit enough. I've never seen an electric panel fo anything other than put some vents to allow heat to flow out. But u know what u r doing

[@FatgirlMickey]

@@OffGridGarageAustralia also i love watching your videos even if I'm not building what u r.

[@FatgirlMickey]

@@OffGridGarageAustralia let me say also that I'm not an electrical engineer so I'm not saying that what you're doing is wrong I've just never seen that in any electrical panel I've ever worked in and I was electrician commercial for 14 years

[@MrSummitville]

@@FatgirlMickey So, you have never worked on electrical cabinet that had Solar Inverter & Charge Controllers mounted inside. If you had, then you would know ...

[@dankarau2307]

For intake...you could put ductwork down to the floor to get the coolest air!

[@OffGridGarageAustralia]

Not much cooler down there. It's sunny hot Australia

[@chrisfryer3118]

or even an underground trench, for even cooler, but you may run into humidity problems

[@chrisfryer3118]

If all the fans ran in parallel, you wouldn't have an issue with the differing voltages of the input and exhaust, other than neither being 48v.

[@TheComputerGuyDR]

If you search for "magnetic fan filter" you should be able to find better filters for fans. They are normally in computers and last quite a lot. I also like Positive pressure more than negative pressure cases. They tend to say a tad cooler. For anyone who doesn't know, Positive pressure is when you have more fans blowing in than exhausting. This causes air to escape where it can and generally pulls cooler air in.

[@iainkay3630]

This does depend on how much heat you have to deal with though. I required negative pressure whilst trying to cool an array of graphics cards and ASIC miners putting out 80-90c each hunting for new bitcoins. Managed to get the room ambient temps down to 35c. Ended up using one of those tents that the cannabis growers use (cheaper than building my own tunnel or enclosure but don’t look great!) as they have loads of vent positions and hooked up some 323 m3/hr ventilation fans to that. That’s the only time I’ve found I really had to think about airflow and negative pressure made a good difference there. I do think trial and error is the best way to optimise your cooling set up though. What works for me may not for you!

[@jasondevine6014]

I like your fans. Linky..

[@bassobalalaikka5005]

You might want to connect a 16V Zener or 12V transient supressor (like MPTE12) across each 12V fan in case one of the fans fails, to protect its inside from getting full 48V as the 16V or 25V capacitors insife it might explode. a 1A inline fuse would also protect the system from overvoltage.

[@jmaus2k]

Series fans shouldn't work. Well obviously, you will find out if they do, but on paper the one easiest to turn will spin the fastest and the harder to turn ones will stop or spin slow. Let's see on the next video if you have already ordered a DC/DC converter to step the 48-60V to 12V and connected in parallel again.

[@OffGridGarageAustralia]

Why would the not work? You can series two identical electric motors without issues.

[@zuluwars2996]

All that gorgeous parallel wiring undone - could of just got a buck convertor and that would do the job - Also means if one of the fans goes out you wouldn't burn the the other 3 out with over voltage.... I'm not sure how many volts the fans can take before blowing??? Anyway I love your video's they're inspiring me to get on with creating my own off grid battery setup.

[@OffGridGarageAustralia]

Thank you. I could have installed a buck converter but would need to order one which delays everything again.

[@jasondevine6014]

Don't run fans in series. I have tried. You could add some 12v zeners and a cap across each fan. That would probably work. Btw I use a standard 240 plugpack running off the 48v to provide a 12v output. An easy way to run fans...

[@OffGridGarageAustralia]

Why would it not work?

[@jasondevine6014]

@@OffGridGarageAustralia I think the fans bldc controller doesn't regulate the voltage across them in any constant manner. I did this with 24v and they smoked.

[@teardowndan5364]

@@OffGridGarageAustralia Voltage imbalance between fan will likely fry them sooner or later. 12V zeners is too low though since that's only 48V, which is less than the battery pack. Need to use something around 15V so zeners only pass current when there is a significant imbalance between fans. Also, you probably want intake fans for redundancy: if one or more exhaust fans fail, they'll just suck air back in through the failed fans, you won't have much fresh air circulation from bottom to top.

[@Aconda]

Yes!

[@shivharis]

One could simply put the Inverter's Fan to use - provide vents in the box above the inverter and tunnel the inverter's exhaust out of the box. Or move inverter 1 inch up. Drill holes in the bottom of the box to let new air come in. This solution deploys 'mechanics' vs 'electric.

[@billbean4130]

I have some experience . In the Texas southwest desert we have had years worth of heat problems , cooking lead acid battery's , charge controllers ,and inverters .. first i figured out the biggest heat was the batteries i built a wood box and burred them on the north side of a shed . i put thin wall 3 inch pvc elbow on both sides one with a screen and the other with a 10 ft piece of pipe long painted flat black. i was today surprised how much air it moved by draft, did the same with a three ft piece above the roof . to the electrical room problem solved , no power needed for fans . so on a sunny day more solar input more heat output the more the black pipe heat rise . Mo more issues .

[@jamesbsa6450]

Great idea, @Bill Bean, Texan here as well. So a 10' black 3" pvc chimney for natural convection or upflow draft, and a short ground level screened cold air intake, no fans. That sound right?

[@offgridbydesign3826]

Looks great! One suggestion if you haven't done it yet, add a temperature sensor so the fans don't run all of the time. Unless the controller has and input you can connect the fans to for this.

[@OffGridGarageAustralia]

The inverter has already a temp sensor and switches the fans on when needed.

[@neliosamch3195]

No very efficient ventilation system. Natural air flow would be better if there were 3 fan on top and 4 at the bottom.

[@alex.shenanigans]

Definitely, I was not expecting a @LinusTechTips reference here. Very fine work Andy, keep going!

[@OffGridGarageAustralia]

Hey, thanks!

[@daveorr2192]

are you sure your heat problem is not radiant heat from the steel wall of your shop behind the box ?

[@OffGridGarageAustralia]

Yes, because this is the East wall. I also measured this several times in my previous videos 😉

[@insideoutdesigns1085]

I always look forward to your videos. Thank you for sharing your experience with us. I have a suggestion about your dust filters. If it where me, I would put them on all of the openings, not for the dust but as a bug and spider deterrent. Those little pests love warm areas so I would do what I could to keep them from getting into the cabinet and nesting in the equipment.

[@dstedman8040]

Hi just a thought but maybe a metal cabinet isn't the best idea as it acts like an oven, it's like rapping roast beef in tin foil to keep it warm.

[@paulvos3676]

Nice Andy , i follow your 3 channels to, ich sprechen ein bischen Duetsh. I am from Belgium only 40 km from Aachen ,i get all my computer hardware from Aachen. Now i live on Tenerife and have alot off time to see your nice entertainment videos

[@OffGridGarageAustralia]

Cool, thanks Paul!

[@PatricksDIY]

I look forward to your videos!

[@OffGridGarageAustralia]

Yay! Thank you!

[@guy7gsa]

Mee two

[@davidjackson8787]

Nice work.

[@sarathai2876]

I enjoy your welcoming music to your videos. I made it the ringtone on my phone. So now when the phone rings I think solar. I live in Florida East Coast 360 days of sun per year

[@OffGridGarageAustralia]

Thank you very much. That is crazy, hahaha.

[@danfitzpatrick4112]

Nobody would learn without making mistakes. That's why we love you brother! And we love the excitement too! This is why your channel is so successful.

[@theonlywoody2shoes]

Those who choose not to learn (and make mistakes doing so) are destined to remain as single cell organisms swimming around in their pond of primordial soup - got to love experimentation and progress (and an occasional error) and who doesn’t love Andy’s enthusiasm.

[@OffGridGarageAustralia]

You're the best, Dan!

[@jamest.5001]

I think I'd use a DC buck converter and a tempature controlled relay!

[@MrSummitville]

Nope, the inverter supplies all that is needed ...

[@TBL_stevennelson]

You can Under Volt them. Less Noise, Power, and Might Last Longer

[@OffGridGarageAustralia]

120mm fans don't make any noise at all. They are in computers and are running for years without any problem.

[@olvano]

use a buck converter and a panel for good output at 12v

[@OffGridGarageAustralia]

Would be another part inside the cabinet. considered it for a moment but 48V is much better.

[@SkypowerwithKarl]

Just cut the top, bottom and and sides out, but keep 1” wide corners. Then install expanded metal over the openings. No fan noise, no fan power wasted.

[@OffGridGarageAustralia]

That would be the worst solution ever. All insects would come in and start nesting. I explained this already in previous videos. I would not need the enclosure at all then 🤷‍♂️

[@SkypowerwithKarl]

@@OffGridGarageAustralia Then fly screen over the openings.

[@jdawes4403]

Take the door off

[@OffGridGarageAustralia]

I did!

[@edwardvanhazendonk]

If the fans run to fast put 1 extra in series on the inlet, that will slow them a bit down or use a small step down inverter to feed them a lower voltage.

[@JeremyAkersInAustin]

The three holes for intake is fine. The air will simply flow at a faster velocity through the intake than it does through the exhaust. Those fans don't move anywhere near the amount of air that could potentially be moved through that size opening (200 cfm max). Look at how much air a leaf blower can push through a much smaller opening. Your intake vent is plenty big enough.

[@jamest.5001]

Cutting a very expensive enclosure, yep a bit of pucker factor there!

[@jungleplant]

you should have put 2 fans low and 2 fans high on the door bottom blows in top sucks out you have weakened the door by getting to close to the sides

[@GEORGE-jf2vz]

I'd stay away what Linus says. He likes to throw things around and behave like a spoiled 5 year old.

[@jmaus2k]

Yay, the fans will go in. Happy electronics now. The door is a good idea too.

[@dayleedwards3521]

The first rule with any installation that must be relied on is to keep it SIMPLE. Complex systems fail more often. Passive cooling is what is needed. here. Drop the box to floor level, add a chimney from the box top to the ceiling to create air flow. This is getting stupidly complicated for what it is.. .... and expensive. A few more additions it will not ever pay for itself.

[@MStrickkk]

Linus knows his stuff for sure, even if he doesn't look that smart :D

[@errolcain4071]

Put a fan each in the cabinet at the bottom on each side

[@toneault7499]

sorry but no mr gecko. you may not come in.. lololol

[@kcdaniels58]

You make learning FUN 😀

[@sreekumarUSA]

040121/1719h PST 🇺🇸 040221/1019h Brisbane. Please mount fan as low as possible.not in the middle or top. The hot air which is less denser will rise upwards. The middle or top design will make less impact, on cooling the system. The metal box will also act as Faraday’s Cage effect, thus preventing Bluetooth TX/RX signals to attenuate. Take care , 73s...

[@OffGridGarageAustralia]

All wrong. The fans at the top are blowing out as explained. Even with the doors closed the BT still works fine.

[@kennith.]

HAHA was a parallel world ....

[@FutureSystem738]

Nice solution Andy- looks good. As far as space is concerned, you could always mount another controller on the side of the cabinet. You could also perhaps even have seven fans all running in series, (ie: three pushing and four sucking) thus running under speed and quieter. They’d also likely then last longer too. BTW What sort of strange people give you a thumbs down on these videos?

[@OffGridGarageAustralia]

Thanks, Dave. Some good ideas!

[@edc1569]

I think you'll have issues running all those PC BLDC fans in series, at power up they'll see all sorts of voltages across their individual terminals and will probably blow out the ICs

[@ebenwaterman5858]

May...be The easy way is to do it and see. Fans are cheap. But you are right. :)

[@jasondevine6014]

I have done it and it does not work

[@OffGridGarageAustralia]

They will run fine. They are just normal fans with brushless motors. You can install as many in series as you want.

[@edc1569]

@@OffGridGarageAustralia when you power them up, they will have for a brief moment all sorts of voltages across their terminals when wired in series, you might get away with 50V but much higher and the MOSFETs in the BLDC controllers will definitely breakdown. Anyway, its a non critical component of your system, so don't worry about it, hopefully it never causes you grief. Thanks for the videos - I'm enjoying them!

[@mikenewman4078]

Andy, the way we always ventilate cabinets in industry is to pressurised them from the bottom and exhaust the hot air from the top. Pressurisation both keeps dirt out and causes better contact with the air for enhanced heat removal. In summary fans at the bottom of the door vents at the top. Fit filters to both inlet and outlet maintain the necessary back pressure and also keep ants out. You don't want ants moving in, they piss formic acid. Rittal make all the necessary equipment which is expensive and requires a fair bit of depth. Doing your own way is more affordable.

[@OffGridGarageAustralia]

Thanks Mike, good tip.

[@marcobrian1619]

Andy....we are all human, we all make mistakes from time to time... We the gods was looking down on you, you realised your mistake and corrected it. Great job!¡!!

[@OffGridGarageAustralia]

Hahaha, yeah, that how it feels like sometimes 😂

[@randylenart9674]

Oh no there's heat!!!! 🤥

[@b.morris2816]

I noticed that one of your fans was not a PWM fan but the other three you could add a PWM controller and adjust the speed of you need too. Or you want to make it quieter for when you are filming more great videos!!

[@OffGridGarageAustralia]

None of them are PWM fans. It then would have a 4th wire.

[@knarf3985]

Hi Kannst du mir auf die schnelke sagen, was ich fuer eine oder2 5kw off grid anlagen bezahlen muss? Danke deiner rueckantwaort

[@steveokinevo]

Easy solution leave the door off 👌

[@MrSummitville]

Bugs ...

[@DavidLouthan]

Happy Easter my good man! This is looking really great! Love this fan system in parallel lol 😆😂

[@adamsherman]

Fans should blow air in, so you have control over the dust filtration. Blowing air out means you may get dust ingress through any little gap or cable entry gland.

[@MiguelSilva-mb6mb]

Why didn't you put 4 filters for intake? You are creating resistance for the fan's to pull air. You are reducing the air flow like that. The size of the intake should match the fans size.

[@OffGridGarageAustralia]

Then I would need 7 or 8 intakes as the filters lower the airflow a lot!

[@alexandergunda8916]

Hi Andy, happy Easter to you too! Btw. in Australia the Easter Eggs are brought by the Kangaroos or by the Koalas? From the easy to mount standpoint - the door is the way to do it. On the other hand from the cooling and air flow perspective top and bottom would be the right way to go - too late anyway. Also putting the fans at the cold (intake) side is more efficient. As you may know, coler air is more dense therefore the fans are working more efficient. But the most important thing is now to properly direct the air flow inside the cabinet. Always remeber, nature is by definition lasy, it takes always the easiest way - therfore you will have to force it a little bit (have a look how data centers are designt).

[@OffGridGarageAustralia]

We have an Easter Crocodile which not only eats all the eggs but also the kangar... anyway... Happy Easter! Cold air, we are talking around 25°... not sure how much denser this is then 35° air. This will not make a difference at all, I believe.

[@waynehobbs5175]

In Australia easter eggs are delivered by our native Bilby.

[@jamess1787]

8 120mm fans is way overkill. It'll drive you nuts. Thanks for the video.

[@OffGridGarageAustralia]

You cannot hear them at all.

[@stevelamperta865]

For starters , why not use the enclosure box for equipment that should be in an enclosure ?? The equipment you have in the box right now isn't designed to be in an enclosure , thus making it hard for it to cool itself.

[@OffGridGarageAustralia]

For starters, do you own such equipment at all? That's totally wrong what you're saying here. If you ready the manual for the inverter for example, it clearly says designed for boats, RVs and cabins. In all of that, you usually have very tight spaces to fit this equipment. If you read further in the manual, you will also find information about mounting the inverter in an enclosure and that you can connect external fans to the inverter.

[@dig1035]

Brother, too much CFM! Also, wired in series defeats fail over for the 120's, respectfully!

[@MrSummitville]

How often do the fans in your PC fail ?

[@jamesdk5417]

Thanks for your humour. You brighten my day.

[@OffGridGarageAustralia]

Thanks James ☺

[@123hoffie]

You want airflow through box not a cyclone! You want a bit of dwell time for the air in the box to absorb heat not just rush through, you can compare it to a coolant thermostat in an ICE. Run fans in series 12 volts for reduced speed and annoying noise😎

[@MrSummitville]

The job of those fans is to remove the hot from the cabinet. What "noise" are you talking about ?

[@itroy3039]

I would suggest a temperature sensor The fans would only turn on when needed

[@OffGridGarageAustralia]

The inverter has already a temp sensor and switches the fans on when needed.

[@bobbypearson6258]

Put computer fans in cabinet one in and one out They use vary little

[@OffGridGarageAustralia]

These are computer fans.

[@GEORGE-jf2vz]

If each fan is 48 volts you want them in parallel.

[@OffGridGarageAustralia]

They are computer fans running on 12V-18V each

[@dig1035]

Thumbs up and subscribed!

[@OffGridGarageAustralia]

Welcome aboard! Thank you.

[@jeffjohnsisland5551]

Started watching a few days ago. I have enjoyed following along. It is amazing the cost of boxes like you have. Check out a Hoffman network box with double swing and the back plate. I think the box may be made of gold, at least that's what the manufacture thinks. I like to have fan and filter blowing in, so the cabinet is positive pressure. I have filters on the outlet as well, for two reasons. Sometimes the fan is off for extended periods of time and the filter reduces the dust coming in and second, creepy crawly critters are somewhat lessened by the filter.

[@carstenpedersen4067]

2 blowing out 2 blowing in

[@OffGridGarageAustralia]

4 blowing out, 3 blowing in 😉

[@Rajesh_Singh301]

I have installed a 12 volt thermostat connected to a relay, which is then connected to a pedestal fan and an exhaust fan. Threshold temperature is 30 celcius. Setup works just fine and keeps everything nice and cool.

[@b.morris2816]

Oh, I see that it looks like you cut the yellow wire so no PWM control option anymore.

[@Sylvan_dB]

The yellow wire is just a pulse output to measure the speed of the motor. PWM on the power leads works just fine without it.

[@OffGridGarageAustralia]

Not needed, I want them on full power. As Sylvan said these is just a sensor cable. The PWM is done by another circuit receiving the RPM sense from the yellow cable.

[@ebenwaterman5858]

A lot of comments about hooking up smart fans in series. Good point. Maybe chk voltage across each when running.

[@brynsmith414]

I would have installed the fans on the bottom and top of the box, hot air rises and the cooling path will be better that your fan in door solution as a direct path offered the least resistance But any attempt at reducing heat is a great idea and will help reduce the life of those products. Keep up the good work and I enjoy your enthusiasm

[@bradquinn4161]

Putting exhausts in a top facing orientation in a questionable environment is a bad idea. It makes it too easy for stuff to drop into the case. Particularly when the fans are not running. Intakes on the bottom do not have this issue, so I would agree about this style of intakes.

[@brynsmith414]

@@bradquinn4161 it’ll be unlikely in that environment, if anyone was concerned then a strip of fly mesh would sort that issue, we use these fans for cooling, mainly the magnetic version as they produce less noise. I’m just putting out another way to do it out there.

[@bradquinn4161]

@@brynsmith414 Yeah, we tried that in our shop and after a few years had no end of problems. Moving the upper vents to an orientation perpendicular to the top vastly reduced the issues. Remember, the fans do NOT run all the time. They are controlled by the equipment. Any form of debris (even dust) entering into the case will cause problems.

[@brynsmith414]

@@bradquinn4161 that odd you are having issues, i guess it varies on the workshop and the suspended airborne material. I realise that the fans don't run all the time, no one would, unless it was producing heat 24/7. we run ours through a thermo switch and also voltage controller to reduce noise when needed if in a noise sensitive area

[@iainkay3630]

That’s turned out looking really nice man. I know from experience that airflow can be a right pain in the ass to get right so I’ll be following closely to see how this goes in practise!

[@SigmaWorksSW3D]

yess, finaly cooling ;) they look great in those doors :)

[@bobfoulke4875]

Nice!! I think you need to add an Arduino pcm fan control with a Temp sensor to move the air only when needed

[@andrewwhittaker6622]

I don't like fans Just another thing to go wrong I used 75mm storm water PVC out through the roof with a bend and a screen And another to near ground level with a screen Natural airflow with the chimney effect Same setup on my 240v fridge freezer to assist cooling

[@OffGridGarageAustralia]

Won't work here in Australia. Also, more inlets for insects to come in. and, there is no space for a 75mm pipe in my enclosure.

[@andrewwhittaker6622]

@@OffGridGarageAustralia flange on top and bottom of the enclosure! Nothing goes inside the box Mine works fine on the South West Slopes of NSW Max temp sometimes get to 46c in summer Just gives a nice gentle air flow I use the same for excess Hydrogen extraction from the battery banks Simple but effective Cheers

[@mikoserbousek4987]

Only two issues I see with this: One, it relies on outdoor ambient temperature. Really unavoidable, as climate control is impractical here. Two, there's no account for moisture/humidity. Depends on where you live how much this is a problem. I can't get away with a setup like this (inside a cabinet outside of my bus) as conditions outside could easily be detrimental to operation. You likely can. Both are environmental factors, probably which you're comfortable with.

[@mikoserbousek4987]

Btw, if you want to you could step down from 48V to 12V and then use an automatic fan controller to regulate fan speed. Using standard computer fans you have lots of selection.

[@OffGridGarageAustralia]

Moisture is not a problem here, super dry all year around.

[@vwtrike9546]

I know this is a little off topic but not sure where to ask?.Does the Victron smartshunt show current as small as .2amps?.I currently use another shunt but it does not see the current constantly drawn by a raspberry pi,which means if there were no charging the battery i am using could go flat in 5-7days and the current shunt would still say 100% SOC.

[@OffGridGarageAustralia]

Yes, it shows current done to 0.1A and even this is adjustable in the app.

[@JeremyAkersInAustin]

@@OffGridGarageAustralia It shows the current down to 0.1 but it's not very accurate at those low current levels in my experience.

[@dtec30]

in Fanuc robotics cases they have a "z" type cooling configuration which keeps the inside clean by having a separator in the middle to keep dust out you could do this with a heatsink to transmit heat from the inside to the outside fans on the outside push air along the heatsink and fans on the inside pull air along the heatsink one set of fans is at the top and the other set of fans is at the bottom on either side of the heatsink

[@OffGridGarageAustralia]

That sound complicated and a lot of effort. Not sure if I would have enough space inside the cabinet.

[@dtec30]

@@OffGridGarageAustralia your already half way there

[@dtec30]

can i send you a pic ? might explain it better.