Tales from a Ventilation Lunatic

[regis101]

SW wrote: 

Hmmmmm, seems my attempt to attenuate my general contempt for modern humans, is failing. 

So it goes.

Yeah, but we luv ya.

[sternwake]

The Delta FFB1212EHE  120mm x 38mm fan was tested at different voltages, for amp draw.

  Amperage readings were taken before the Drok 80 watt buck/boost  voltage converter with a clamp ampmeter over the + wire. I have not added the 10 turn/3600 degree potentiometer to this converter yet, it is using a 270 degree pot and as such is a bit difficult to dial into a precise voltage as fractions of a degree equal a tenth of a volt. Very light touch required.

 Output Voltage is as displayed by the Drok 80 watt buck booster.

Input voltage  a short distance away, circuit wise, under no load, was 12.231v.

The wiring feeding Drok buck boost voltage converter was about 24 inches of 22 awg zip wire and some ~3 foot long  insulated 18awg alligator clips.   There is significant voltage drop on this feed wiring at higher amperages, though I did not measure it. The Drok voltmeter will toggle between input and output voltage, but I forgot to toggle it to see how much drop there is at higher amperages.  The voltage drop on this undersized wiring, will effect the efficiency of the drok converter, especially when boosting voltage above input voltage.

I should have used more significant and shorter wiring for a more accurate wattage reading.

The impeller will not start spinning until the fan is fed 6.98, or more, volts.
Once it is spinning, one can lower voltage to as low as 6.28 volts before it stops spinning, but it is moving almost no Air at this speed.

I have an old  rusty 120mm fan grill on the intake side of this fan.  Restrictions in front of, and behind fan will affect amp draw.

@ 6.28 volts   it draws 0.15amps.  That is 0.942 watts
@ 7.03 v................0.43 amps.  3.03 watts
@ 7.54v.................0.72a..........5.43watts 
@ 8.05v.................0.92a...........7.4 watts
@ 8.56v.................1.10a.............9.42 watts
@8.99v..................1.22a..............10.97 watts
@9.50v...................1.39a..............13.25 watts
@10.0v...................1.59amps.........15.9watts
@10.5v...................1.80a................18.9 watts
@11.0v...................2.00a.................22 watts
@12.0v ..................2.45a..................29.40 watts
@13.0v...................3.07a..................39.91 watts
@14.0v...................3.61a...................50.54 watts
@15.0v...................4.20a....................63 watts
@15.4v....................4.45a....................68.53 watts
@15.6v....................4.62a.....................72.07 watts
@16.0v.................... 4.85 amps..............77.6 watts

The drok buck booster is rated at 80 watts with additional cooling, 60 continuous.  I stopped there. If I ever have a flooded battery again,  and equalize it at 16.2v, the maximum I could then feed the fan with a 5 amp bucker only power supply,  is 15.9v.
Its unlikely I'll ever feed this fan more than 14.4volts.

One can see the wattage consumed more than doubles at 15v compared to 12volts, at least through this drok buck boost voltage  converter

Above 14v the airflow and noise starts becoming violent and unpleasant, up in 252 cfm delta screaming banshee territory. The banshee fan at 12.0v  battery voltage, not through any converter, draws 2.85 amps or 34.2 watts.

I have no intention of running the 80watt Drok buck/boost converter  on this fan, I will run a 5 amp bucker only, which I expect to be slightly more efficient, but actual data will reveal the truth as to how much. 

At 0.55 amps of draw (in the 7.25 volt range), which is the amperage my existing ceiling fans inline  can consume at max speed, I'd say the airflow is very similar, meaning I should be able to exhaust just as much air as I do now, for the same amperage consumed, but I have a whole lot more power to tap into.  the whole voltage range from 7.25 to within 0.3v of battery voltage.  

At what point no more air can be forced through my mushroom vent in its current configuration, is unknown, but generally it is a high  static pressure rating which is desired for restrictions in front of fan blades.

The silverstone fm121 is rated at 110 cfm and 3.26 mm of static pressure
The arctic cool ARCTIC F12 PRO PWM PST fan is 53 cfm and 2.54mm  static pressure
Combined lets say they together
, in line, they  could move 163cfm and 5.80mm static pressure, even though they cant.

The new delta fan is rated at 190 cfm and 17.78mm static pressure.
Capable of 3+ times as much pressure. and similar efficiency/performance at the max amperage of existing fan set up

Insert maniacal laughter here.
This delta fan is going on my ceiling, no doubt.

The screaming Banshee Delta fan started a lot of my interest in manipulating fan speeds on fans that do not have that option out of the box.  Below 7v and it just shuts off and it is still way too loud and powerful  and drawing over 2 amps. Not acceptable for use in the van.
The new Delta fan can be speed controlled via voltage,  and is nearly as powerful as the Banshee.

My 92mm delta clamp fans are actually louder with a more annoying pitch than the 120mm Banshee when cranked all the way up,  but they cant take over that name.

I have 2 versions of the 5 amp voltage buckers.
One of them has a current limiting potentiometer. 
I could limit the fan to 0.5 amps or anywhere above that, up to 5 amps.I dont know if the version with the current control pot is as efficient as the one without it.

Time will tell, as I will collect data using both.
This new delta fan is a PWM fan.
Will it respond to my Noctua NAfc-1 PWM fan speed controller, or will it smoke that controller?
IS controlling its speed via the 4th wire, the PWM wire, significantly more efficient than speed control by voltage?

I suspect so.

Time will tell.

[sternwake]

The 24v Papst Clamp fan got much closer to its final configuration tonight.

The previous buck/boost power supply I had mounted inside the aluminum C portion, smoked itself the day after installation. Not a huge disappointment, as it was incredibly inefficient powering the fan.

   

I have a 10 amp buck/boost power supply That has both voltage and current trimpots, these are 200K ohm, where other power supplies the trimpots were 10k or 50K ohm.  Bourns does not make 200K 10 turn pots, nor 150k ohm either.

I wound up ordering a new old stock 150K ohm OHMITE single turn potentiometer. I like the box it came in.
   

One issue with all my previous speed controlled fans, is that when I'd turn the pot all the way down, and the fan stops well before the dial is all the way down.  It takes a while to stop, and if one is merely trying to slow the fan as low as it can go, one has to be there to spin the dial to the right level, instead of just cranking it down and walking away.  It is time consuming to dial the fans down to low speed without stopping.

 It is likely not good for the fan to be fed 5 volts, when it will not start until it gets 7.8 volts.  it would also waste battery power doing this, performing no work other than creating heat.

I ordered a 150K ohm pot, intending to add a 50k OHM trimpot inline, so instead of going to zero resistance turned all the way down  the 150k pot  would only lower as much as I have the 50K ohm trim pot set.  50K ohms runs the Papst fan at 8.xx something volts.

The papst fan will spin as low as 7.46 volts, but it will not start spinning on its own from a dead stop until 7.79 volts.

I dialed down the 50k ohm trimpot until the minimum voltage with Ohmite pot turned all the way down was 7.79 volts.  Maximum voltage is then close to 29 volts with Ohmite pot turned all the way up.

If necessary, I can get lower fan speeds by dialing down the 50k trimpot with the jeweler's screwdriver, and I can get higher speeds than 29 by dialing it up.

But I don't want speeds much above than 29 volts, as amp draw increases significantly over 29v, without all that much extra fan speed, and the fan is rated to 30v.

I soldered a 50k ohm trimpot terminal,  right to a terminal on the Ohmite potentiometer, and used some amazing goop and the third unused terminal on the potentiometer to hold it in place.  So my Ohmite pot grew a trimpot wart.

Dual voltage potentiometers in series.

   

I got a 6 inch microphone gooseneck instead of the 16 or 18 inch  one which could not support the weight of the Papst fan when horizontal.  

   

The 10 amp buck/boost power supply has no issues when I spin the voltage dial quickly from 7.79 volts to 29, where as the 80w drok, would stall and display a fault on the voltmeter and the fan would slow to a stop.  It would not restart until turned way back down, down then slowly raised back up.

The Ohmite pot, is actually only 140.7K ohms, not 150. This actually limits the voltage to 29, which is kind of perfect.  If were 150K ohms then I could dial in voltages well north of 30. However, I could use the current pot to limit amps to 2.32 and it would then be incapable of exceeding 29 volts powering this fan.

I am quite happy with the function of this powerful clamp anywhere fan.  I need some sort of fingerguard, on the face of the fan, and a way to support some airfilter material I will form into a column the circumference of the fan extending many inches behind it, for lots of surface area and minimal restriction to airflow.  A round pleated car air filter or two of the correct diameter would also work nicely to filter out workshop dust, and should not affect airflow much at all.

I'll likely trim some excess aluminum, paint it black, mount the voltmeter somewhere highly visible but out of the way, and paint much of it black.  The voltmeter is not really a requirement anymore though, since I can't exceed its safe speed range, low or high.

Before the recent assembly, I was running this power supply loose and using the jewelers screwdriver to adjust speedas its flow in the workshop was required.  Somehow, perhaps I shorted something on the underside of the circuitboard, I blew the 10 amp glass fuse on the power supply.  It's not an easy to replace fuse.

I used my insulated flag terminal dies inside my Anderson powerpole crimper, to make my own ATC fuse holder.

   

I was bummed the holes in the circuit board for the fuse, did not allow for thicker wire, but so be it, I'll not be passing 10 amps through this device anyway.

I put a 7.5amp  fuse in it, while the supply is rated at 10 amps and the fan draws under 2.5 at 29v.
The fuse is easily accessed and replaced.

The Ohmite pot came with a locking nut to prevent spinning the shaft. The part of the shaft one could grasp, was only 1/8 inches thick. It did not come with a knob.

My old 12v mattress heating pad's adjustment knob basically fits perfectly, and has a locking set screw on the side.

[rvpopeye]

Nice workaround with the trim pot.

I think you're getting this fan issue sussed out close to a final device !

[sternwake]

Thanks.
I am quite happy to have confined the 24v Papst clamp on fan to nearly its full usable speed range by twisting one potentiometer. Its airflow is impressive for the amp draw and noise produced at 29 voltsn and really at any voltage, but some fans are certainly even quieter with less amp draw down low.

Ideally, the fan would allow the minimum rotational speed of 7.43 volts, instead of the minimum start up speed of 7.8 volts, but if i need lower speeds all I need to do is bust out the jeweler's screwdriver and twist. and keep in mind that if I unplug the fan, that it will not restart on its own at 7.43 volts.

Which is basically what i have had to do with every other fan since I started manipulating voltage and fan speeds on fans which do not leave the factory with a speed controller.

The 24v Papst clamp fan is less desirable inside the van, due to the larger size and to a lesser degree, higher weight. The 92mm delta powered clamp fans are extremely capable of doing their task, of blasting my body with fast moving filtered air, but are obnoxiously loud at high speeds and still a full 106cfm short of the 24v papst fan at 29v. The velocity of air and the force behind it is more than that of the Papst though. The 92mm deltas cranked high and aimed at my sweaty t shirt after a long fiona walk yields the chills in seconds and lower rpms soon after. That power is appreciated, greatly.

i actually don't know at what voltage the Papst fan achieves 283 cfm, could be 24, could be 30v.

The Papst fans seem to be built like tanks. I think the one that I smoked must have smoked because of the sub 5$ boost buck power supply i was testing it with, but it could also have been a dud. Its amazing that the Papst fan is only 10$ + shipping, granted they want 15$ to ship it, but shipping 4 fans adds only $1.50 to that shipping price. The modern equivalent 24v papst fan, is a minimum 116$ . So these discontinued ones for 10$ is an absolute steal.

I've no idea how long this link will be valid, but here is the 10 amp buck boost power supply which is currently powering the 24v papst clamp fan. I've ordered another, even though I don't have a use for it at this time.

https://www.ebay.com/itm/10A-DC-DC-BUCK-...100623.m-1

With it at 29 volts for 15+ minutes passing ~2.3 amps to the papst fan, , the hottest part of the b/b power supply was the wirewound toroid at 99.8f. The hottest part of any heatsink was 72f in 68f ambient. This thing is not stressed at all powering the Papst fan, apparently, and as such 'should' be reliable long term, and it has no issues providing the surge amperage when I demand 29v. quickly, whereas I had to turn the potentiometer much slower with other power supplies or they would overload.

There is a processor chip on the underside I suspected might get hot and benefit from more heatsinking, but it only achieved 84f so I said F it.

In previous posts I raved about the efficacy of the 6$ Jaro fans, but I regret seeing that 200 cfm rating, and not exploring whether Delta had similar CFM offerings in a 120mm x 38mm computer fan and explored the net for prices.

Even at 14$, the delta fan is way better, as it has no detectable vibration, responds to voltage control from banshee to silent speeds, and exudes quality all around.

I have ordered 3 more Deltas ffb 1212 EHE's to phase out the Jaros, even though I really don't need to spend the money or time on replacing them, especially with winter coming.

While I rarely need the airflow at the high speeds at which the Jaros start vibrating, when I do, it would be nice if they did not start vibrating the whole van. I cranked the new window shroud fans upto the max last night briefly after making some smoke inside, and Fiona got quite alarmed. The one which I failed to improve its balance of the impeller, making it worse instead, sounded like it was going to fall apart if I left it going at max speed. BUt I was also plugged in with at 14.7v so the fans were able to get close to 14.4v, and they earn their 200 cfm rating at 12.0v.

The interior seemed to drop 12 degrees in about a minute with those Jaros blasting away. Could imitate the blazing saddles bean scene, and smell nothing. The deltas will be able to do the same without vibration and mess noise, but with more reliability.

[sternwake]

Was enjoying the speed range of the papst tonight.
Fan speed goes up, then goes down.
Fan speed goes up, then goes down.
Fan speed goes up, then goes down.
Fan speed goes up, then goes down.
Up down up down 

Then voltmeter goes out and fan stops.


Nooooooooooooooooooooooooooooo!



My insulated flag terminal crimper ATC fuse holder, did not adequately crimp over the quad folded 24awg wire It pulled right off the wire. 
Should have expected that, instead of hoping it would not.

I have decided to relocate the fuse near the Anderson Powerpole, and soldered the 18 awg power wires( from a failed 1990's dremel) to the circuit board to avoid the circuit board fuse and the dang screw terminals which crush wire under a screw then quickly loosen up and allow wire to pull/fall out.

I had covered the terminals on underside of circuit board with  cured Amazing goop. It peeled off cleanly with some precision tweezers with chisel like flat tips, which made me happy and allowed easy soldering to bypass the circuit board fuse.

[sternwake]

I now have 4 of the 190 cfm Delta 120mm fans, and one of them is now employed on my ceiling, forcing air out of the Nicro 4" mushroom vent through a 4.75" to 4.0" cedar step down ring.

For over a decade I have been running a silverstone fm121 there, with an Arctic cool open frame counter rotating fan as a pusher fan that increased flow and reduced noise. 

I Was pretty impressed with this combo.

However, The 190 cfm  Delta fan is several orders of magnitude more effective at max speed, and at the same 0.55 amps as the other 2 fans at their max speed, is also more effective for about the same noise level. different pitch though.

The new semi screaming banshee Delta fan seems indifferent to the counter rotating fan at most rpms, and it likely just presents a restriction at medium to high rpm.  I'll not bother employing the CR pusher fan anymore on the ceiling, and I gain a little more clearance for taking things off the shelf over front seats.

Lowest possible fan speed is somewhere around 0.06 amps, which is lower than the silverstone fm121s minimum of 0.09x. It is quieter too.

The 18 awg circuit feeding this fan could certainly be improved upon. When battery voltage is at 13.6v, and the fan cranked upto full speed, voltage at the voltage bucker on the fan is 11.91v, and the output is 11.61v,  It moves an insane amount of air at 11.61 volts. There seems little need to upgrade the wiring for less voltage drop and even more air movement as it is loud and unpleasant enough at 11.61v. and it draws 1.65 amps at that voltage.
 
I might, perhaps,  be able to resist feeding it 10AWG.

I have done the same series trimpot potentiometer with the main potentiometer as I did on the Papst fan, so that when I lower the main 10 turn pot all the way, the fan does not shut off.  The full range of speed is achieved in about 1.25 of those turns, which is more convenient than 5 or 10 turns, but it is still easy to dial in a very low speed above the minimum,  unlike 3/4 turn pots.
   

The fan will not start on its own at this minimum speed, but if I dial it to the lowest possible starting speed, 5.37 volts, then the fans spins a bit too fast and loud, and I don't intend on shutting it off often.

I have not yet adhered the voltage bucker to the fan with Amazing goop, or routed the wires. The Silverstone pot had the small 2 wire connector, so i wired that same connector to it, and I used a 4 wire connector, using only two wires as the power feed, so i can easily remove the fan from the wiring to clean it.  If I wanted to pull down some wires or solder wires awkwardly over my head, I could have used all 4 wires in the 4 wire connector for both pot and power feed.
   

The cedar and walnut step down ring that I made in 2008, will likely get modified with my dremel and a rotary rasp to align more with the steering vanes and help reduce restriction, and perhaps noise.

   


The acrylic front window shroud with the poorly balanced Jaro fans, is also getting the Delta fans and the same minimum speed limiter. The rotatable grill which directs airflow down at Fiona, works much much better with the Delta fan than with the Jaro.  The Jaro, the flow flattened out and spread wide and seemed to restrict the fan's  flow a good amount while increasing noise, but with the Delta fan the flow stays in a narrow column but is directed at an angle away from fan face, and it does not seem diminished much at all by the rotatable grill's friction restriction and noise increase is not as pronounced as when th grille is placed infront of the Jaro.

The rear  acrylic intake  shroud 120Mm Jaro fan, will also be getting a Delta Fan Replacement.

I have acquired a 60 amp peak/ 40 amp constant PWM 21KHZ motor speed controller suitable for a brushed motor, like the Hvac blower motor Dodge installed. I want to see how much air this blower motor moves and amperage it uses at various  speeds, and  be able to power it with the engine off.  I will perhaps wire it up more permanently so i have infinite speeds. instead of 4  stock speeds through the inefficient resistor packs.  That project could get tabled for a bit though.

[rvpopeye]

AND.
The winner is........Delta !

Enjoying the fruits of your experiments.
Priceless.

[sternwake]

The Delta fan is awesomely powerful.

Last night I turned off my intake fans, but left the window open just enough so the silverstone fm181 had free access to air behind it. When I cranked up the new ceiling exhaust delta, even with poor door seals, the amount of air sucked in through the intake shroud was nearly as much as the silverstone fm181 fan on its slowest speed, and if I turned on the silverstone briefly to get its impeller spinning, the Delta fan was able to keep the impeller spinning once I turned the SS fan off.

I bet an analog barometer inside the van, could be influenced by the Delta fan getting only 11.6v. NOw if I were able to get it 14.4v with thicker wiring feeding it. It would collapse the van walls like a soda can

[rvpopeye]

Then I guess that's one experiment you probably shouldn't try. skuh kuh kuh kuh kuh